The Land of Hot Water was a small country, but its beautiful scenery and numerous therapeutic hot springs had made it the favorite holiday destination of travelers in the shinobi world.
As a result, the Land of Hot Water had accumulated considerable wealth.
With money came the inevitable need to develop military strength for self-defense.
The Land of Hot Water's former Daimyo had been an ambitious man. As he set about establishing Yugakure, he also began investing heavily in training ninja.
Just as the country was taking a turn for the better, the Daimyo went out on an excursion and drowned in a dried-up hot spring.
The newly appointed Daimyo launched an investigation. The ninja from his own village believed the Daimyo had been assassinated, but the ninja teams hired from Konohagakure and Kumogakure unanimously concluded that he had gotten drunk and drowned.
Never mind how the Daimyo had drowned in a dried-up hot spring. That was the conclusion, regardless.
From then on, the newly appointed Daimyo abandoned his efforts to govern well and began indulging freely in drinking and debauchery.
Before long, a small-scale war broke out in the Land of Hot Water.
Konohagakure and Kumogakure were the two warring sides. They had barely lost even a handful of Genin in the fighting, yet the Land of Hot Water suffered a devastating blow.
Civilian casualties were heavy, and the newly established Yugakure was caught up in the war and thoroughly destroyed before it could train many ninja.
And so, after the war ended, all subsequent ninja missions in the Land of Hot Water were entrusted to Konohagakure and Kumogakure. As for their own barely surviving Yugakure, no one dared mention it again.
This was the tacit understanding between the Five Great Nations: no small nation would be allowed to