was a after Tenbun and before Eiroku. This period spanned the years from October 1555 through February 1558. Reigning emperors were and .

Change of era

  • 1555 : The era name was changed to mark an event or a number of events. The old era ended and a new once commenced in Tenbun 24.

The name originates from the following Chinese passage: 「祇承宝命、志弘治体」.

Events of the Kōji era

  • 1555 (Kōji 1, 1st month): A border war began between Mōri Motonari, daimyō of Aki Province, and Sue Harukata, daimyō of Suō Province.
  • 1555 (Kōji 1, 11th month): The Mōri forces surrounded the Sue defenders in the Battle of Itsukushima. When the outcome of the battle became clear, Sue Harutaka committed suicide; and others, including Odomo-no Yoshinaga, followed Harutaka in suicide. This victory, and the subsequent consolidation of the Mōri holdings were owing to Motonari's four sons: Mōri Takamoto, Kikkawa Motoharu, Hoda Motokiyo, and Kobayakawa Takakage.
  • 1556 (Kōji 2): The Ōmori silver mine fell into the control of the Mōri clan during a campaign in Iwami Province.
  • September 27, 1557 (Kōji 3, 5th day of the 9th month)<!-- NengoCalc 弘治三年九月五日 -->: Emperor Go-Nara died at age 62.