Second Shinobi World War

The was the second of three great wars involving the majority of the shinobi villages and countries. Not much is known about the politics of this era, but there were known conflicts between Konohagakure, led by the Third Hokage, Sunagakure, likely led by the Third Kazekage, Amegakure, led by Salamander Hanzō, and Iwagakure. The majority of the fighting seems to have taken place in minor countries like Amegakure, leaving them devastated. The eventual outcome of the war seems to have been in favour of Konoha.

As with all wars, the Second Great Shinobi World War brought forth many heroes and took even more lives. It was during this war the legendary Sannin rose to fame and received their nickname from Hanzō during a skirmish with Amegakure. Tsunade in particular became famous as the world's greatest medical-nin while successfully countering all of Chiyo's poisons. It was also likely the war where Sakumo Hatake made name as Konoha's White Fang.

On the other side, it was the war where Tsunade lost her younger brother Nawaki and her lover Dan, leaving her with an extreme case of hæmophobia. It was possibly the war that took the lives of Sasori's parents, an event that eventually led him to desert his village and join Akatsuki.

The war left many countries in ruins. In the aftermath, Jiraiya decided to take care of three young orphans from Amegakure, claiming it was the least he could do. He eventually discovered that one of the orphans, Nagato wielded the legendary Rinnegan. The experiences he had during this war made Nagato desperately search for peace, eventually becoming the entity known as Pain, successfully staging a coup d'etat in Amegakure, overthrowing Hanzō, and co-founding Akatsuki.