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The Sengoku period (戦国時代, Sengoku Jidai, "Warring States period") is a period in Japanese history of near-constant civil war, social upheaval, and political intrigue from 1467 to 1615. The Sengoku period was initiated by the Ōnin War in 1467 which collapsed the feudal system of Japan under the Ashikaga Shogunate.