During the Warring States Period, ninja clans abounded.
The Uchiha were among the least likable of them, known as a clan of lunatics.
They fought viciously and held grudges.
Of course, the most hated ninja clan was actually the Kaguya Clan, Kimimaro's family.
They had originally lived in the Land of Fire and had been on fairly good terms with the Hyuga Clan.
But for the sake of commissions, they took on missions like mad, earning the name "the mad dogs of the battlefield."
Even the Uchiha couldn't stand them.
Those bastards charged straight in, biting and tearing. If they had no weapons, they used their bones instead.
In the middle of a fight, your opponent's bones would suddenly sprout and impale you. Hereditary bloodline diseases ran rampant among them, and everyone who entered the battlefield was there purely to enjoy one last good fight before dying.
You fought to survive or improve your life. They might well have been fighting just for the thrill.
How were you supposed to fight that?
The Uchiha would trade an injury for a kill and never backed down.
The Kaguya Clan, on the other hand, sought to trade their lives for an injury. If you flinched, you died.
Eventually, the Senju and Uchiha couldn't take it anymore. They spearheaded an alliance with the Sarutobi, Ino-Shika-Cho, Hagoromo Clan, and other ninja clans to drive the Kaguya Clan out.
At the coast, they took another vicious beating from the Uzumaki Clan and the Senju Clan and Uchiha Clan pursuing them.
In the end, they were forced into the Land of Water, where they started playing island warfare with several local ninja clans.
How could those clans in the Land of Water, isolated from the outside world for so long, have ever encountered mad dogs like