was a Japanese daimyo

Daimyo

is a generic term referring to the powerful territorial lords in pre-modern Japan who ruled most of the country from their vast, hereditary land holdings...

 of the Sengoku period

Sengoku period

The or Warring States period in Japanese history was a time of social upheaval, political intrigue, and nearly constant military conflict that lasted roughly from the middle of the 15th century to the beginning of the 17th century. The name "Sengoku" was adopted by Japanese historians in reference...

. He was born in Bizen Province

Bizen Province

was a province of Japan on the Inland Sea side of Honshū, in what is today the southeastern part of Okayama Prefecture. It was sometimes called , with Bitchu and Bingo Provinces. Bizen borders Mimasaka, Harima, and Bitchū Provinces....

, to Ukita Okiie, a local samurai leader. After the assassination of Naoie's grandfather Yoshiie in 1534, he was left homeless along with his father, but both were soon taken in by Murakami Munekage, the lord of Tenjinzan Castle. Naoie succeeded to family headship in 1536, after his father's death.

Mimura Iechika

Mimura Iechika

was a Japanese daimyo of the Sengoku period. The son of Mimura Munechika, he was the lord of Matsuyama Castle, in Bitchū Province...

, a rival warlord, was murdered on Naoie's orders.