Bun'ei
Bun'ei ( Japanese 文 永 ) is an annual motto ( Nengō ) of the historical Japanese calendar . It falls under the reigns of the Kameyama - and the Go-Uda - tennō in the middle Kamakura period . According to the Gregorian calendar , it refers to the period from February 28, 1264 to April 25, 1275.
The first Mongol invasion occurred during the Battle of Bun'ei .