Kunio
The small planet of Kunio, placed deep within the Outer Rim, would remain untouched, completely secluded for ages. A lush ripe planet, with substantial vegetation and four seasons, it consists of one major continent, the rest being water, and smaller patches of land scattered throughout it's 4 hemispheres.
The positioning of Kunio's suns, the vegetation, the favorable weather conditions would all play a part in the molding of Kunio's people. For these reasons and other unknown factors, the Kunians would become the very pinnacle of a humanoid life form. Faster, stronger, far more intellectual than any other known species.
The Kunians would eventually split into three major clans. The Shi, the Iga, and the Orochi. These three people would split the major continent of Kunio into three large regions. The Shi would take the Shonan region, the Iga the Kaeda region, and the Orochi the Odagiri region. When Kunio exactly broke out into war, is unknown. Some say it is when Hattori Hanzo of the Iga challenged Haomaru of the Shi, some say it was when the three regions were split, and some say it was when the first life form stood on two feet.
Nonetheless, Kunio's history would be painted in blood.
The Iga would eventually slaughter the Orochi, driving it's people from their rightful land, and claiming it their own. Their numbers would swell, driving the Shi back into the recesses of Shonan. They would rape, they would plunder, and day by day, the Shi would decrease in number. The Iga took their time, letting the Shi suffer, knowing that victory would eventually be theirs. They had never expected the birth of three demons from the folds of the Shi.