The Warring States Era. A time period in which Shinobi constantly battled over territory, power, and politics. Not one day passed when blood was not shed, causing it to later be referred to as the darkest of times. Five pillars of light gave their lives to bring the continent to peace, so they say.
During this time, the land was split into 5 sectors: North, West, East, South, and the Central Desert. The four directionals belonged exclusively to the feudal Ninja tribes, and the Central territory became a safe haven for the long-ridiculed Samurai. It was here that the Samurai built a flourishing land where none of ill intent may enter, but all are welcome. Their long-standing leader, Xu Shen Han, fought the gluttonous Shinobi for what felt to be an endless time, granting him not only the title of "Strongest Samurai", but also the entire Desert area as his own to govern and protect.
As for the other four Ninja territories, they remained divided and far more prejudice. The North, commanded by Tsuki Kaguya, head of the infamously savage Kaguya clan, was mountainous and bore many earthly resources for its inhabitants. Tsuki lead his land with an iron fist, gaining complete control and respect of his people. This made it very easy for the North to dominate the Land of Stars, a small colony in the Western quarter, belonging to Kyumaru Chinmoko. Kyumaru was a greedy man who looked only at the value of his lands and treasures, but also valued brotherhood over everything. Though his property value was being threatened, he let it pass for various political reasons. Not to mention, the Kaguya clan-head was rumored to be immortal for doing the deeds of the devil himself.
On the opposite continent, the flourishing Eastern grounds were tarnished with the blood and carcasses of smaller clans and enemies to the Sato clan. Akihiro Sato ruled over the Eastern quarter with a fist as strong as if it had been forged from steel born of the Land of Iron itself. He was a tyrannical leader with many daughters and no true heir. It bothered him not, seeing that he hoped to gain the same immortality as the Kaguya. The family man was driven mad with the wild idea that the Devil would notice him if he conducted business in the most sinful ways possible, slaughtering unaligned tribes, raping and pillaging campsites, as well as taking all the land for himself along the way.
These clashing personalities contributed to the collapse of the way of the Shinobi, and all hope that one day they'd come together for an Era of peace and prosperity.