c. 800--Viking raids on Pictavia begin. First Norse settlements in the Shetland and Hebrides islands. Other raiders hit monasteries and towns on the coast of Britannia.

c. 800 onward--The feudal system develops among the Franks and begins to spread across Europe.

802--Vikings sack the monastery at Iona.

804--Crown Prince Custennin ap Cadwallon marries Eilfgiva, daughter of King Aelle III of Sussex.

805--For a second time, Vikings sack the monastery at Iona. A son is born to Crown Prince Custennin. The boy is named Owain ap Custennin of the House of Ambrosius (or House of Emrys, as it is increasingly referred to in the Kingdom as the use of Latin declines). Prince Owain is shortly afterward anointed as King of Gwynedd.

807--King Conall mac Taidg of Dal Riada is killed in battle by Conall mac Aedan, who takes the throne for himself.

808--Sigered’s Rebellion: With the active support of Emperor Charlemagne of the Franks (whose long wars with the various pagans and infidels on his borders are finally winding down) and Pope Leo III, the exiled pretender to the throne of Essex, Sigered, is able to return to his kingdom , backed by a small force of Frankish troops. Slipping past the British fleet in three ships, they land near Colchester (the former city of Camulodunum, which had become the capital of Essex after the destruction of the Kingdom of Camulod in the mid sixth century). The Saxon inhabitants of the area, most of whom still remain staunchly Roman Catholic, rally to his banner, and spurred on by Frankish and papal agents, Roman Catholics in Deywr and Kent (now ruled by Sussex) also rise in rebellion. Roman Catholics in the former Kingdom of Wessex on the Isle of Wight, the only other place in Britannia with a Roman Catholic majority population, do not rise up in revolt, perhaps realizing the futility of such action and hoping for mercy from the High King in the inevitable backlash which is sure to follow. Unfortunately for them, they will not escape the High King’s wrath.

High King Cadwallon ap Peredyr being of advanced age and in ill health, the British response is coordinated by Crown Prince Custennin ap Cadwallon, who is also the commander of the Byddin Mawreddog. Custennin calls upon his allies in East Anglia and Sussex to provide troops, which they do, and these forces, combined with the Byddin Mawreddog and other troops from the High King’s own lands, are sufficient to deal with the rebellion without ever calling up the forces of the British sub-Kings. Charlemagne attempts to send reinforcements for the rebellion across the Oceanus Britannicus, but Charlemagne’s fleet is intercepted by a combined British and East Anglian fleet off the coast near Colchester and defeated. Only a few Frankish ships manage to get through and land their troops, with the rest of them being turned back, captured, or destroyed. Without these reinforcements, Sigered’s force in Essex is defeated and destroyed less than six months after landing, and the rebellions in Deywr and Kent fare no better. Sigered is killed in the final battle outside Colchester, along with his sons, bringing final extinction to the House of Essex.

In the aftermath, High King Cadwallon can clearly see that the rebellion was sponsored by the Pope, and realizes that as long as there is a significant minority of Roman Catholics within his kingdom, there will likely be unrest and even rebellion. And so, supported by Kings Aelle III of Sussex and King Eadwald of East Anglia, Cadwallon orders the Saxons of Essex and Wessex, the Jutes of Kent, and the Angles of Deywr to either renounce their allegiance to the Roman Church or face exile. Many of them do renounce the Roman church and take oaths of loyalty to the High King, but most refuse. Thousands of Angles, Saxons, and Jutes take ship and go into exile in Francia. Roman Catholic churches and monasteries are seized and their Roman priests are forced to leave the country. British or Anglo-Saxon priests who adhere to the British church are installed in their places. It is a dark day for Roman Catholics in Britannia.

810--After gathering troops and shipping for two years, Charlemagne attempts an invasion of Britannia, but his fleet is once again defeated by the combined naval forces of Britannia, Sussex, and East Anglia off the coast near Dover. The Franks are completely unsuccessful in their attempts to land troops, and thousands find watery graves in the Oceanus Britannicus when their vessels are destroyed or captured. It is the worst defeat Charlemagne will ever suffer during his reign, and the depression which it causes the aged Emperor will contribute to his death the following year.

811--Conall mac Aedan is defeated and killed by Domnall mac Caustantin, son of King Caustantin mac Fergus of Pictavia. Caustantin becomes King of Dal Riada. Death of the Emperor Charlemagne at Aachen. He is succeeded by Louis the Pious. Shortly thereafter, the Bretons revolt against the Franks, but are defeated.

812--Death of High King Cadwallon ap Peredyr. He is succeeded by his son, Custennin ap Cadwallon.

812-835--Reign of High King Custennin ap Cadwallon. Most of Custennin’s reign will be spent dealing, not very successfully, with the Viking threat. The Bagan Gogleddwyr ("Pagan Northmen"), as they will be known in Britannia, will ravage numerous towns and monasteries on the British coastline during his reign. Viking raiders will appear suddenly from the sea, strike without warning, and then disappear before the High King can rally his forces to respond. Even the existence of the British navy created by High King Cadwallon ap Peredyr does little to stem to tide of Viking depredations, as the need to maintain most of the fleet on station in the Oceanus Britannicus to defend against a possible Frankish cross-channel incursion means that few ships are available to patrol the rest of Britannia’s coastlines.

818--Louis the Pious issues a diploma in favor of the Breton abbey of Landevennec after the victory at Priziac. The Emperor orders Abbot Matmonoc to revise the Breton church to match Frankish practices, rather than Celtic practices. He further attaches all Breton diocese to the Archdiocese of Tours. Another Breton revolt against the Franks is defeated.

820--Death of King Caustantin mac Fergus of Pictavia and Dal Riada. He is succeeded in Dal Riada by his son, Domnall mac Caustantin, and in Pictavia by his brother, Oengus mac Fergus, who rules as King Oengus II. The Vikings conquer the Isle of Man and establish a permanent base there. Also in this year, thirteen Norse ships reach the Seine Bay. A force of Vikings lands but, having to face the shore guard, they are forced to re-embark, leaving five of their number dead on the Neustrian shore.

820-841--Reign of King Feidlimid mac Cremthanin of Munster Feidlimid will spend most of his reign warring, burning monasteries and ravaging rival kingdoms across Ireland. In the end, he will briefly make himself High King of Ireland...for one year, in 840. His defeat and death in battle the following year at the hands of Niall Caille mac Áeda will bring Niall to the High King’s throne. But Ireland is much weakened by Feidlimid’s destructive campaigns...just in time for the Vikings to take full advantage when they arrive.

822--Yet another Breton revolt against the Franks is crushed.

824--Breton leader Guihmarc'h leads a rebellion and is captured by Emperor Louis the Pious. Louis releases him with gifts and allows him to return to Brittany.

825--Death of King Eadwald of East Anglia. He is succeeded by Aethelstan.

826--Count Lambert of Nantes kills Breton leader Guihmarc'h, who is in revolt again.

828--Crown Prince Owain ap Custennin marries Briallen, daughter of King Dungarth of Dumnonia.

829--King Aelle III of Sussex dies, and is succeeded by Watta

830--Emperor Louis the Pious names Nomenoe, a Breton native noble, as imperial "fidelis as missus" of Brittany. This is the first Frankish acknowledgment of Brittany as a single political unit. Nomenoe will remain loyal to Louis until Louis's death.

832--King Oengus II of the Picts and King Domnall of the Scots join forces to raid into Strathclyde and Gododdin. The Dux Brittaniarum, King Mynyddog ap Llud of Gododdin, raises a force to respond and surrounds the Picts and Scots at a river crossing about 20 miles east of Din Eidyn, capital of Gododdin. The night before the battle, St. Andrew appears to King Oengus of the Picts in a dream, promising him victory, and the next day, both sides see clouds forming what appears to be a white Cross of St. Andrew against the blue background of the sky. The Picts and Scots, remembering Oengus’s dream, are emboldened by this apparent "miracle," and proceed to inflict a heavy defeat on the British army. However, despite the victory, the Picts and Scots retreat across the border to their own homelands, knowing that more British forces (including the Byddin Mawreddog) are on the way. In thanks for the victory and for their lucky escape, King Oengus and King Domnall both decide to adopt St. Andrew as the patron Saint of their respective nations, and in memory of this event, the white cross of St. Andrew on a blue field will one day be the national flag of the united nation of Scotland.

834--Death of King Oengus II mac Fergus of Pictavia. He is succeeded by Drust mac Caustantin, nephew of Oengus and son of former King Caustantin mac Fergus. A son is born to Crown Prince Owain ap Custennin. The boy is named Cynan ap Owain of the House of Ambrosius/Emrys, and is anointed as King of Gwynedd shortly thereafter. Also in this year, Viking raiders attempt to raid up the River Tafwys (Thames), but are met by the British fleet and defeated.

835--Death of King Domnall mac Caustantin of Dal Riada. He is succeeded by Aed mac Boanta, a member of the family of former King Aed Find mac Echdach. Viking raids on the Kingdom of Dumnonia. Also in this year, High King Custennin ap Cadwallon is killed in battle with Viking raiders near Eborac. Crown Prince Owain succeeds to the throne, and Prince Cynan is anointed as King of Gwynedd. The Isle of Sheppey comes under Viking attack.

835-867--Reign of High King Owain ap Custennin. Like his father, the chief problem faced by High King Owain during this reign will be the continuing raids of the Bagan Gogleddwyr (the Vikings). During his reign the nature of those raids will gradually change from mere plundering expeditions to serious invasions aimed at territorial conquest.

836 onward--Viking chieftains Björn and Hasting lead numerous raids in Cotentin and Avranchin, in Francia.

836--A Viking army of approximately 1700 men aboard 35 ships invades the Kingdom of Dumnonia and defeats the army of King Dungarth, who is killed, along with his sons. The Vikings proceed to ravage Dumnonia. However, they shortly thereafter are met near the village of Carrum (OTL Carhampton) by an army of 3,000 men under the command of Arthur ap Custennin, younger brother of High King Owain, consisting of units of the Byddin Mawreddog, the armies of the kingdoms of Sussex, Pengwern and Powys, the remnants of the army of Dumnonia, and the levies of Dwrn Gwarae and Caer Gwinntguic. In a sanguinary fight, the heavily outnumbered Vikings are defeated. Pursued by the British cavalry, few escape to their ships. In the aftermath, the throne of Dumnonia is left without a legitimate heir, and at the meeting of the Cyngor Mawr called later that year to discuss the matter, High King Owain ap Custennin declines to claim the kingdom for his own. Instead, as a reward for his defeat of the invaders, the kingdom is awarded to Prince Arthur ap Custennin, who founds a new royal dynasty for Dumnonia.

837--Death of King Drust mac Caustantin of Pictavia. He is succeeded by Eoganan mac Oengus, son of King Oengus II mac Fergus.

839--Kings Aed mac Boanta of Dal Riada and Eoganan mac Oengus of Pictavia are killed in battle with the Vikings. Pictavia fragments into several competing kingdoms. In Dal Riada, Alpin mac Echdach (son of Eochaid mac Aed Find) assumes the throne. Death of King Aethelstan of East Anglia. He is succeeded by Aethelweard. A large Viking fleet under the command of Thorgest arrives in Ireland, sails up the Shannon and Bann rivers to Armagh, which he captures. Thorgest settles down and forms the first Viking kingdom in Ireland, spanning Ulster, Connacht and Meath.

840--Viking raids turn temporarily away from Britannia as the Frankish Empire is weakened by the death of Emperor Louis the Pious. Civil war breaks out in the Frankish Empire among the sons of Louis. Nominoe of Brittany supports Charles the Bald in the civil war.

841--Vikings under Ivar the Boneless and Olaf the White found Dublin in Ireland. Other settlements will soon follow, including Limerick, Waterford, and Wexford. Also in this year, Asgeir's Viking fleet sails up the River Seine (from 12th May), takes the city of Rouen (14th May) and burns it down. The loot is enormous. Aesgir's army continues its penetration of the Seine, plunders and burns the rich monastery at Jumiege (24th May). The nearby monastery of Fontenelle is also assaulted and held to ransom. In this expedition, sixty-eight captives are taken and then returned on payment of a ransom by the monks of Saint-Denis (28th May).

843--Death of King Alpin mac Echdach of Dal Riada in battle with the Picts. He is succeeded by his son, Cinead mac Alpin (Kenneth mac Alpin). Treaty of Verdun...the Frankish Empire is divided between the three sons of Louis the Pious. Charles the Bald inherits the western portion, Lothar the middle parts, and Louis the German inherits in the east. The Vikings sack Nantes in Brittany.

845--Thorgest, who had established a Viking kingdom in Ulster, Connacht and Meath, is killed by Mael Seachlainn I, King of Mide. Mael Seachlainn becomes High King of Ireland shortly thereafter following the death of High King Niall Caille mac Áeda . Ragnar Lodbrok’s fleet of 120 ships (therefore c. 6000 men) sails up the Seine and besieges Paris. Charles the Bald pays 7000 livres in order to spare Paris. Later that year, Ragnar’s ship is blown off course and he lands in East Anglia. He is arrested and taken to the court of High King Owain ap Custennin, at Caer Camulod. Owain considers Ragnar to be a pirate and little better than a common criminal, and orders him hanged. Upon hearing of his death, Ragnar’s son, Ivar the Boneless, swears revenge. In Brittany, Charles the Bald is defeated by the Bretons at the Battle of Baldon, near the town of Redon. High King Niall Caille mac Áeda

845-860--Reign of Mael Seachlainn I, High King of Ireland. Mael Seachlainn will enjoy some success in his wars against the Vikings. He will also attempt to form a united front against the pagan invaders with other kingdoms similarly threatened. Arguing that all Christendom should ally against the pagans, he will send requests for aid to Charles the Bald of the Franks and to High King Owain ap Custennin of Britannia. Charles the Bald will ignore the request, but High King Owain will send some troops and ships to aid the Irish.

846-847--Vikings ravage Brittany, threatening Nomenoe’s rule. Nominoe bribes them to leave.

848--Irish High King Mael Seachlainn defeats a Viking army at Sciath Nechtain.

849--Nomenoe dismisses all the bishops of Brittany in favor of his own appointments from 'his own race and language.' This is effectively a declaration of war against the authority of Charles the Bald.

850--Cinead mac Alpin (Kenneth mac Alpin) of Dal Riada defeats and kills the last of the Pictish kings, Drust mac Fethal, assuming the Pictish throne shortly afterward. The Kingdoms of Dal Riada and Pictavia are permanently united, becoming the Kingdom of Alba. It will eventually become known as Scotland. Nomenoe of Brittany attacks Rennes, Nantes and Le Mans.

850-858--King Cinead mac Alpin (Kenneth mac Alpin) of Alba invades Gododdin and Strathclyde eight times in as many years. His incursions are repelled, with difficulty, by British forces under the command of the Dux Brittaniarum, King Merfyn of Strathclyde.

851--Viking Raids on Gwynedd and Dyfed. Asgeir and his men, back on the Seine, this time devastate the monastery of Fontenelle and return there eighty-nine days later (9th January 852) and, finding nothing to plunder, burn it down. Death of Nomenoe of Brittany suddenly deep in Frankish territory at Vendome; Nomenoe dies, undefeated, after conquering the counties of Maine and Anjou. He is succeeded by his son Erispoe, who will be the first to be styled "King of Brittany" after defeating Charles the Bald at the three day battle of Jengland and then again at the Battle of Ballon. However, Erispoe still acknowledges fealty to Charles the Bald. Another Viking force lands in the Kingdom of Dumnonia. King Arthur ap Custennin of Dumnonia is defeated, but escapes. The Danes ravage the kingdom, then withdraw with their plunder, before High King Owain can marshal a response. This is due mainly to the fact that, at the same time, Owain is dealing with Viking threats on his eastern shores, where another Viking fleet attempts to invade via the Tafwys (Thames), but is intercepted by the British naval squadron based at Caer Lundein and defeated. And yet another Viking fleet is defeated by British and Sussexian squadrons off the coast of Kent.

852--Asgeir and his force raid on foot in the Beauvais region (Flanders county), from their base in Rouen. Engaged by a Frankish army, they have to withdraw and camp for the winter on Jeufosse island, securely controlling the entrance to the Seine. They stay there until June. By the end of this year, a new group of Vikings, mainly Norwegians led by Sigtrygg (back from Ireland) and Godfrid, sails up the Seine to Jeufosse to establish their own base there. The Frankish army of Charles the Bald besieges the island. Also in this year, a Viking army lands on the Isle of Thanet, off the coast of Kent. They establish a base and winter there. The British are unable to expel them.

853--Charles the Bald negotiates with Godfrid, who afterwards retires. As for Sigtrygg, he stays to plunder and burn numerous places up until March of this year. The Vikings plunder Nantes again. King Erispoe of Brittany declares war on them and will fight them for two years, until the Vikings leave the area.

855--Death of King Aethelweard of East Anglia. With his passing the House of Icel becomes extinct, and as the closest living relative, High King Owain ap Custennin claims the throne of the Kingdom. The Witanagemot of East Anglia votes to accept his claim, and the Kingdom of East Anglia peacefully passes into the control of the British High King, as did it’s sister kingdom of Lindsay before it. Also in this year, Viking chief Sigtrygg returns to attempt to destroy a Frankish fort located on the Seine shore on the approach to Paris. He is reinforced by Björn, leading a powerful fleet. The two armies join and carry out a raid in the south of the Seine, as far as Chartres, where they are stopped by the Frankish army of Charles the Bald. They have to withdraw to the Seine after heavy losses. Anglesey is devastated by Vikings from Dublin. Also in this year, Viking army under Ivar the Boneless and Halfdan Ragnarsson, both sons of Ragnar Lodbrok, attempts an invasion of Britannia from Ireland. They land in Rheged, where they defeat the army raised by the local governor (Llywodraethwr), who withdraws into his fortified capital, Caer Leol (OTL Carlisle) and there withstands a siege. But High King Owain, in cooperation with the Dux Brittaniarum, King Madog ap Gwalchmai of Strathclyde, brings a large force to the succor of his governor, and the British are successful in raising the siege, inflicting a sharp defeat on the enemy army. Ivar and Halfdan retreat across the Irish Sea to Dublin.

856--A large Viking invasion of Gwynedd takes place, lead by a chieftain named Gorm. The armies of Gwynedd and Powys, lead by Crown Prince Cynan, defeat the Vikings and Gorm is killed in the battle.

857--Again from Jeufosse, which has now become an established base, Sigtrygg's and Björn's armies attack Paris. Later that same year, Chartres is assaulted again; on this occasion, revenging the reverse of AD 855, they take it, plunder it, and slaughter all its population. During the summer they also attack Evreux and many other places, the action taking place generally around Jeufosse island. Finally, Sigtrygg retires with his men. King Erispoe of Brittany is murdered by his cousin, Saloman, who usurps the throne.

858--Björn is joined by a new group of Danes, led by Hasting. They lay again into the abbey of Fontenelle, which they burn down. Leading a mounted force, Björn surrounds Paris and demands a ransom of the Parisian monasteries. Charles the Bald is defeated when he reacts and tries again to besiege the Viking base of Jeufosse. Death of King Cinead (Kenneth) mac Alpin of Alba. He is succeeded by his brother, Domnall (Donald) mac Alpin.

859--The attacks from the Seine valley are redoubled. Charles the Bald is engaged in a struggle with his brother, Louis the German. The Vikings take advantage of this to attack freely far from their bases: Bayeux, Laon and Beauvais, where the bishops are executed.

Crown Prince Cynan ap Owain marries Moira, daughter of High King Mael Seachlainn I of Ireland.

860--The Viking chief, Weland, is paid 3000 silver livres by Charles the Bald to try to drive out the Vikings of the lower Seine. Also in this year, the Vikings discover Iceland.

861--From May, Weland besieges Jeufosse island, leading 200 Viking ships. The Vikings of Jeufosse have to retire from the Seine, with some 100 ships. This fleet then joins Weland's. Taking advantage of several years of respite, Charles the Bald builds forts which control the Seine at Pont-de-l'Arche.

862--Death of King Domnall mac Alpin of Alba. He is succeeded by his nephew, Constantine mac Kenneth, son of Cinead mac Alpin. Death of High King Mael Seachlainn I of Ireland. He is succeeded by Aed Finliath of the Ui Neill dynasty of Ulster.

863--The Treaty of Entrammes between King Saloman of Brittany and Charles the Bald of the Franks recognizes Anjou as part of the Breton kingdom.

864--A son is born to Crown Prince Cynan ap Owain and Crown Princes Moira. The boy is named Arthur ap Cynan of the House of Emrys (Ambrosius).

865--Fifty Viking ships settle at (near Pont-de-l'Arche), on the Seine. Also in this year, the long-planned revenge of Ivar the Boneless and the other sons of Ragnar Lodbrok is finally sprung upon Britannia when, in the autumn of 865, a large army of primarily Danish Vikings lands in East Anglia, under the command of Ivar and his brothers Halfdan and Ubbe. The size of this host is not precisely known, but estimates range from 150 to 250 ships and anywhere from 7,000 to 15,000 warriors. Although the British fleet (consisting of the Humbri and Tafwys squadrons, along with the fleet of Sussex) attempts to engage them at sea, the sheer size of the Viking fleet overwhelms the British flotilla, most of which is captured. Only a few ragged survivors make it back to Caer Lundein. Upon landing in East Anglia, the Vikings ravage the land, then settle in for the winter in the fortified city of Camulodunum (OTL Colchester).

866--The Viking army of Ivar the Boneless and his brothers, Halfdan Ragnarsson and Ubbe Ragnarsson, moves west, at the head of an army of nearly 10,000 men, from their base in East Anglia toward the British capital at Caer Camulod, bent on revenge against High King Owain, who hanged their father, Ragnar Lodbrok, back in 845. The old High King Owain personally meets them in battle, at the head of a force of approximately 4,000 cavalry and 7,000 infantry (the Byddin Mawreddog and the combined teulus and levies of most of the High King’s provinces, as well as and those of the Kingdoms of Pengwern and Powys), about 20 miles east of Caer Camulod. In an incredibly savage battle, the Vikings are defeated and turned back with heavy losses. However, the cost to the British is nearly as much as that inflicted upon the invaders (over a quarter of the elite Byddin Mawreddog was killed in the battle, for example, and losses among the other contingents of the British host are as great or greater), and Owain is unable to follow up on his victory. The Vikings retreat back to their base in East Anglia and send out a call for reinforcements. Also in this year, another Viking army from Ireland, under the command of Olaf the White, attacks the Kingdom of Alba, but is defeated by King Constantine mac Kenneth.

867--The Frankish king, Charles the Bald, concedes Cotentin and Avranchin to the Bretons, so that they might defend these territories. However, the Bretons, too, are being devastated by the Viking raids, and their sovereignty over these territories will be only theoretical. In Britannia, the Viking Army in East Anglia is reinforced, and it’s leaders, Ivar the Boneless and his brother Halfdan, decide on a new strategy...instead of attacking High King Owain’s capital directly, they will try to split the Kingdom of Britannia by capturing the provinces to the north of Caer Lerion. As a first step, they decide to capture the city of Eborac and use it as a base of operations. Accordingly, in the spring of 867, part of the Viking host marches advances overland (moving rapidly on horseback and ravaging the province of Lindsay as they go) toward Eborac, while the rest sails up the Humber River (where the British naval squadron formerly based there has never recovered following the crushing defeat of 865 and has been withdrawn permanently to Caer Lundein). The two parts of the army combine outside Eborac and lay siege to the city, which falls to them within a few weeks, and the victors establish themselves within Eborac’s fortifications and begin bringing the surrounding country under their control. Later that year, High King Owain attempts to recapture the city, but he is unsuccessful. Owain himself is killed in the battle near the town of Caer Leodis (OTL Leeds), and by the end of the year, the provinces of Deywr, Eborac, and much of Elmet are under Viking control, along with East Anglia. Crown Prince Cynan ap Owain succeeds to the High Kingship upon the death of his father, and his son, Arthur ap Cynan, is installed as King of Gwynedd.

867-880--Reign of High King Cynan ap Owain. Like that of his father and grandfather before him, the problem of the Vikings will consume his reign. Cynan will make several reforms of the military structure of Britannia which will serve the kingdom well in it’s later struggles with the invaders. Cynan answers the Danish threat by creating an impressive system of new fortified Caers throughout his realm (especially in the northern border regions adjoining the Viking kingdom of Jorvik). These Caers will provide a refuge for the people of the surrounding area in case of Viking attack, and will be protected by well-armed garrisons capable of sortieing out and harassing the flanks and rear of a Viking host which might have passed the Caer by without stopping to reduce it first.

Cynan also reforms the levy systems of the provinces and sub-kingdoms, changing it from a sporadic levy into a standing force. He divides the levy into two rotating contingents designed to give some continuity to military actions. Rather than respond to the Vikings with the ad hoc levies of local noblemen which are disbanded when the crisis has passed, the British now will be able to always have a large force in the field to supplement the Byddin Mawreddog.

Cynan also decides to reorganize the infantry contingent of the provincial and sub-kingdom levies. Recognizing the great power of the long bows which have been in use in his western provinces since at least the early seventh century...the arrows of which can punch right through a Viking shield and continue straight on through the mail shirts worn by the Viking warriors with little difficulty...Cynan pushes a law through the Cyngor Mawr which requires each province and sub-Kingdom to equip and train at least half of it’s infantry with this formidable weapon. Gradually, over time,. Cynan and his successor, High King Arthur IV, will evolve highly effective new tactics which take advantage of the firepower this weapon provides. British commanders will use the threat of their formidable cavalry to force the Vikings to stand on the defensive, then decimate them under a hail of arrows before finishing them off with a cavalry charge.

Finally, Cynan and his successor will rebuild and expand the British navy, which by the end of the century will be making a great contribution to British security once again.

868--The Vikings in Eborac are consolidating their gains, and conduct no major campaigns in this year. Given this brief respite, High King Cynan ap Owain reconquers East Anglia, most of whose Viking garrison had taken part in the capture of Eborac and the surrounding regions. Unfortunately, the British find a devastated and mostly depopulated land which has suffered cruelly under the heavy yoke of the Danes. Also in this year, High King Aed Finlaith of Ireland defeats the Danish and Norwegian Vikings at the Battle of Killineery.

869 onward--Period of nearly constant warfare between Britannia and the Viking Kingdom of Jorvik (as they call their conquests in the region around Eborac). For the most part this is a fairly even contest, with victory going as often to the British as to the Vikings. Several large waves of Norse settlers arrive in the wake of the invading armies to settle the newly conquered regions, and the British find it impossible to dislodge them before the end of this century. And the Vikings make no further penetrations into the southern parts of Britannia, but they do manage to conquer Rheged, cutting off Strathclyde and Gododdin from the rest of Britannia, in 875.

870--Harald Luva (Fairhair) starts his effort to gain full control in Norway. Many people who oppose Harald’s rule will emigrate abroad, with many going to the Kingdom of Jorvik. The first Viking settlers arrive in Iceland.

871-872--In 871, a Viking army under King Olaf the White of Dublin and King Ivar the Boneless of Jorvik invades Strathclyde and burns Alcuid, the capital. The Vikings plunder the capital and ravage the surrounding lands, then take their booty to Dublin. Among the prisoners taken...to be sold as slaves in the markets of North Africa and the Middle East...is the King of Strathclyde, who is captured and taken in chains to Dublin, where he is executed. In the aftermath, King Constantine mac Kenneth of Alba invades Strathclyde and attempts to seize the lands. High King Cynan sends a force, commanded by his uncle, Rhodri ap Custennin, to drive out the Scots. Rhodri is successful in doing so. However, the royal house of Strathclyde is now extinct, and High King Cynan claims the Kingdom for his own. He appoints Rhodri ap Custennin as Governor (Llywodraethwr) of Strathclyde.

873--Ivar the Boneless dies in Dublin. His brother Halfdan takes over the rule of Dublin, as well as Jorvik.

874--The first Norse settlements are founded in Iceland. 

874-888--Taking advantage of the civil war between the rival rulers of Brittany, the Vikings invade and overrun Brittany.

874--King Saloman of Brittany is murdered. The kingdom is divided and ruled by Gurvand of Rennes (son-in-law of Nomenoe) and Pasquitan of Vannes (son in law of Saloman). Neither recognizes the right of the other to rule, and civil war breaks out. Halfdan Ragnarsson, who is unpopular because of his excessive cruelty, is deposed by Guthrum. Guthrum assumes the throne of Jorvik and will continue the Viking campaigns against Britannia. Halfdan flees to Dublin.

875-900--The ravaging of Scotland. In 875, Halfdan Ragnarsson, leading an army of Vikings from Ireland and the Hebrides, invades the Kingdom of Alba, where they inflict a heavy defeat on the Picts and Scots. They will stay in Alba for the next quarter century, ravaging the land and settling the northern and western parts of it in large numbers. Vikings will kill King Constantine mac Kenneth in battle in 877, with Halfdan Ragnarsson falling in the same fight. The Vikings are victorious, however, and will find new leadership. Meanwhile, Constantine is succeeded by his brother, Aed mac Kenneth, who is himself killed by the Vikings in 878. Aed is succeeded by Giric mac Dungail, a son-in-law of Kenneth mac Alpin. Giric will reign until 889, when he too, will fall in battle against the Vikings. His successor, Donald mac Constantine, son of King Constantine mac Kenneth, will reign until 900, when he, too, will be killed in battle by Vikings under King Harald Fairhair of Norway. But Harald’s raid will be the beginning of the end of the Viking domination of Alba, as Harald’s real target was not Alba, but the Viking host which had been ravaging it for so many years...said host being composed, in large part, of Norwegians who had fled Norway during Harald’s campaign to unite the country under his rule, and who were now periodically raiding Norway itself.

875--A Viking army from Jorvik conquers Rheged, severing communication between the kingdoms of Gododdin and Strathclyde and the rest of Britannia.

876--100 new Viking ships make an incursion into the Seine. They sail away again after a payment of 5000 livres by Charles the Bald.

877--The Vikings invade Gywnedd. Both Gurvand of Rennes and Pasquitan of Vannes, the joint rulers of Brittany, die. Gurvand is succeeded by his son, Judicael, while Pasquitan is succeeded by his brother, Alan. Neither recognizes the right of the other to rule, and the civil war continues. Death of Emperor Charles the Bald of the Franks. He is succeeded in Western Francia (France) by his son, Louis the Stammerer.

879--Death of King Louis II "the Stammerer" of Western Francia. He is succeeded by his sons, Louis III and Carloman. Death of High King Aed Finlaith of Ireland. He is succeeded by Flann Sinna mac Mael Seachlainn.

879-916--Reign of High King Flann Sinna mac Mael Seachlainn of Ireland. Flann Sinna will spend most of his reign warring, not with the Viking invaders, but against the kings of the lesser Irish kingdoms. Indeed, he will often find himself allied with Norsemen against other Irishmen.

880--Louis III and Carloman divide the Kingdom of Western Francia between them. Louis takes Neustria (the northern part), Carloman takes Burgundy and Aquitaine. High King Cynan ap Owain is killed in battle with the Vikings. His son, Crown Prince Arthur, is only 16 years old at the time...too young to ascend the throne in his own right. His great-uncle, Rhodri ap Custennin, is appointed Rhaglaw (regent) by the Cyngor Mawr (High Council) until Cynan comes of age.

882--Death of King Louis III of Western Francia. He is succeeded by his brother Carloman as sole King of Western Francia. Crown Prince Arthur ap Cynan comes of age and is crowned as High King of Britannia.

882-908--Reign of Arthur IV ap Cynan, High King of Britannia. Like his father, grandfather, and great grandfather before him, Arthur will find his reign consumed with warfare with the Vikings. He will continue his father’s reform of the British military, and by the end of his reign will begin the reconquest of the regions lost to the Norse invaders.

883--In an effort to bind the kingdoms of Britain together into a united front against the Viking threat, High King Arthur IV ap Cynan marries Princess Dechtire, daughter of King Constantine mac Kenneth of Alba.

884--Death of King Carloman of Western Francia. He is succeeded by his uncle (a son of Louis the German), Charles the Fat.

885--A huge fleet sails up the Seine (one report tells of some 700 ships) to besiege Paris. Losses are severe on both sides. The new Frankish king, Charles the Fat, relieves the city by paying a heavy ransom to the besiegers. Harald Fairhair gains full control in Norway, uniting it as a single kingdom for the first time in history.

887--King Charles the Fat of Western Francia is deposed and replaced by Odo, Count of Paris. Odo will fight unsuccessfully against the Vikings under Rolf, and against Charles the Simple, a son of Louis the Stammerer who actually has a better claim to the throne than does Odo himself, throughout his reign.

887-911--Rolf (Rollo/Rollon) imposes himself as chief of the Vikings settled in the lower Seine region. He repels the Franks, pushing right up to the doors of the Ile-de-France. He attacks Chartres but, repulsed, withdraws again to the Seine. Finally, in 911, seeking to block the lower Seine, which had become a real "motorway" for the Viking invasions of the Kingdom of Western Francia, the new king, Charles the Simple, concludes an agreement with Rolf at Saint-Clair-sur-Epte, conceding to him the suzerainty of the territory of the lower Seine which, de facto, Rolf had already had for several years. The region will become known as "Normandy," meaning "land of the Norsemen."

888--Alan of Vannes and Judicael of Rennes, the contending rulers of Brittany, finally put aside their quarrel and join forces to face the Viking threat. The Vikings are defeated at the Battle of Questembert, but Judicael is killed in the fighting. Alan of Vannes is now the sole ruler of Brittany.

890--Death of King Guthrum of Jorvik. He is succeeded by Guthfridh. Guthfridh is a much less able warrior than Guthrum was, and during his reign, the power of the Vikings of Jorvik will begin to wane.

896-- Dyfed and southern Powys are ravaged by Haesten and his Viking pirate army.

898--Death of King Odo of Western Francia. He is succeeded by Charles the Simple.