The Sengoku period was initiated by the Ōnin War in 1467 which collapsed the feudal system of Japan under the Ashikaga Shogunate. Various "samurai" warlords and clans fought for control over Japan in the power vacuum, while the "Ikkō-ikki" emerged to fight against "samurai" rule. The arrival of Europeans in 1543 introduced the arquebus into Japanese warfare, and Japan ended its status as a tributary state of China in 1549. Oda Nobunaga dissolved the Ashikaga Shogunate in 1573 and launched a war of political unification by force, including the Ishiyama Hongan-ji War, until his death in the Honnō-ji Incident in 1582. Nobunaga's successor Toyotomi Hideyoshi completed his campaign to unify Japan and consolidated his rule with numerous influential reforms. Hideyoshi launched the Japanese invasions of Korea in 1592, but their eventual failure damaged his prestige before his death in 1598. Tokugawa Ieyasu displaced Hideyoshi's young son and successor Toyotomi Hideyori at the Battle of Sekigahara in 1600 and re-established the feudal system under the Tokugawa Shogunate. The Sengoku period ended when Toyotomi loyalists were defeated at the siege of Osaka in 1615.