Sengokuperiod

The Sengokuperiod, commonly known as the Sengoku period or Sengoku Jidai in Japanese, was a period of social upheaval and near-constant military conflict in Japan. It lasted roughly from the outbreak of the Ōnin War in 1467 to the early 17th century, when central authority began to coalesce under a new ruling regime. The Ōnin War weakened the Ashikaga shogunate and led to the dispersion of power among regional military lords.

During this era, political authority fragmented as many daimyō—regional warlords—constructed autonomous domains and fortified castle towns. Warfare became more intense and more professional, with alliances shifting frequently. The period also saw significant social and economic changes: increased mobility, rising merchant activity, and the gradual militarization of society. Foreign contact began to influence Japan in the mid-16th century, most notably the introduction of firearms by Europeans, which transformed battlefield tactics and fortification design.

Prominent figures shaped the course of the era. Oda Nobunaga initiated the process of unification in central Honshu, Toyotomi Hideyoshi continued and consolidated reforms, and Tokugawa Ieyasu completed the unification and established the Tokugawa shogunate after decisive victories in the late 1590s and 1600. By 1603, central authority shifted under the Tokugawa regime, and the militarized feudal system gradually gave way to a long period of relative peace and stable governance, often called the Edo period.

The Sengokuperiod left a lasting imprint on Japanese political, military, and cultural development. It shaped the organization of domains, the role and status of the samurai, and the path toward early modern state formation, influencing governance, land use, and urban growth for centuries.