From the testimony of historical documents it can be seen clearly that Yazeed had no religious character at all and that even during the lifetime of his father he was oblivious to the principles and regulations of Islam. 

At that time his only interest was debauchery and frivolity. During his three years of caliphate he was the cause of outrageous calamities that had no precedent in the history of Islam, despite all the strife that had occurred before him. 

During the first year of Yazeed's rule Hussain Ibin Abe Taleb(as), the holy grandson of the Holy Prophet Mohammad(pbuh&hf), was brutally massacred in the most atrocious manner along with his children, relatives, and friends. 

Yazeed even had some of the women and children of the "Holy Household"(as) of The Holy Prophet(pbuh&hf) mercilessly killed and their beheaded heads gruesomely displayed in public in many different cities. 

During the second year of his rule, he ordered a general massacre of Medina and for three days gave his soldiers freedom to kill, loot, and take the women of the City, as they pleased. 

During the third year he had the Sacred Kabah destroyed and then burned to the ground! 

Is this a behavior considered of Muslim let alone the Calipha of Islam?!

Islamic society was dominated by the Arab element alone and non-Arabs were subordinated to the Arabs. Infact a strong Arab empire was created which gave itself the name of an Islamic caliphate. 

During this period some of the caliphas were quite indifferent to religious sentiments to the extent that one of them who was the socalled, "Vicegerent" of The Holy Prophet(pbuh&hf) and was regarded as the protector of religion decided without showing any respect for Islamic practices and the feelings of Muslims to construct a room above the Holy Kabah so that he could have a place to enjoy and amuse himself during the annual pilgrimage. 

It is even recounted of one of these socalled caliphas that he made the Holy Koran a target for his arrows and in a poem composed to the Koran he said: 

"On the Day of Judgment when you appear before God tell Him, that the caliph tore me."

Yet in spite of the unjust and irresponsible ways of the governments of the time the asceticism and purity of the leaders of the Household of The Prophet(pbuh&hf) made the Shi'ites each day ever more determined to hold firm to their beliefs. 

Of particular importance was the tragic death of the Imam Hussain, the third Imam, which played a major role in the spread of Shiasim, especially in regions away from the center of the caliphate, such as Iraq, the Yemen, and Persia. 

This can be seen through the fact that during the period of the fifth Imam Mohammad Al-Baqir(as), before the end of the first Islamic century, and less than forty years after the death of Imam Hussain, the Shi'ites took advantage of the internal differences and weaknesses.in the Umayyad government and began to organize themselves, flocking to the side of the 5th Imam(as). 

People came from all Islamic countries like a flood to his door to collect hadeeth and to learn the Islamic sciences. The first century had not yet ended when a few of the leaders who were influential in the government established the city of Qom in Persia and made it a Shi'ite settlement. 

But even then the Shia continued to live for the most part in hiding and followed their religious life secretly without external manifestations. 

Several times the Descendants of The Prophet(pbuh&hf) rebelled against the injustice of the government, but each time they were defeated and usually lost their lives. The severe and unscrupulous government of the time did not overlook any means of crushing them. 

The body of Zayd 
The leader of Zaydi Shiasim, was dug out of the grave and hanged; then after remaining on the gallows for three years it was brought down and burned, its ashes being thrown to the wind. 

The Shi'ites believe that both the fourth Imam Zain Al-Abdeen(as) and fifthImam Al-Baqir(as) were poisoned by the Umayyads as the 2nd and 3rd Imams had been murdered by them before. 

The calamities brought about by the Umayyads were so open and unveiled that the majority of the Sunnis, although they believed generally that it was their duty to obey the caliphas, felt the pangs of their religious conscience and were forced to divide the caliphas into two groups, 

They came to be distinguish between the, 

'Khulafa Al-Rashidun?' 

Meaning: 

'Rightly Guided caliphs?'

1. Abu Bakr 
2. Umar 
3. Uthman 
4. Ali Ibin Abe Taleb(as) 

The Umayyads caused so much public hatred as a result of their injustice and heedlessness during their rule that after the definitive defeat and death of the last Umayyad caliph his two sons and a number of their family encountered great difficulties in escaping from the capital. No matter where they turned no one would give them shelter. 

Finally after much wandering in the deserts of Nubia, Abyssinia, and Bajawah (between Nubia and Abyssinia) during which many of them died from hunger and thirst, they came to Bab Al-Mandab of the Yemen. 

There they acquired travel expenses from the people through begging and set out for Mecca dressed as porters. In Mecca they finally succeeded in disappearing among the mass of the people without a sign.