Simplify the following text for a Grade 7 native English-speaking person.
Original: Oda Nobunaga June 23 , 1534 -- June 21 , 1582 -RCB- -RCB- was the initiator of the unification of Japan under the rule of the shogun in the late 16th century , a rule that ended only with the opening of Japan to the Western world in 1868 . He was also a major daimyo during the Sengoku period of Japanese history .
Simplified: Oda Nobunaga ( June 23 , 1534 â `` June 21 , 1582 ) was a Japanese daimyo .