During the era before the hidden villages, ninja wore armor that was similar to that of Samurai. It boasted a higher defense than the simple stealth clothing that the shinobi would wear on missions that weren't for battle due to being made of plate armor. Shinobi in Konoha continued to wear the armor until at least the First Shinobi World War, when in the second the transition into Flak Jackets began.
The Akimichi Clan of Konoha seems to have persisted in the use of armor, sometimes even combining it with the current flak jackets.
