1206Ken'ei gannen (建永元年): The new era name was created to mark an event or a number of events. The previous era ended and a new one commenced in Genkyū 3, on the 27th day of the 4th month of 1206.
Events of the Ken'ei era
1206 (Ken'ei 1, 2nd month): Shōgun Sanetomo's standing at court was raised to the 2nd rank of the 4th class.
1206 (Ken'ei 1, 7th day of the 3rd month): The emperor planned to pay a visit to the sesshōKujō Yoshitsune, but in the night before this visit, an unknown assassin was introduced secretly into Yoshitune's house, and he was stabbed by a spear pushed up from below the floor. No one was able to discover the perpetrator. Yoshitsune was then aged 38 years. The sadaijinKonoe Iezane succeeded Yoshitsune as sesshō; and the dainagon Fujiwara no Tadatsune became sadaijin.