太上皇
When GoFukakusa ascended to the throne in 1246 at the age of four, his father GoSaga continued to rule from his position of Retired Emperor. In 1260 GoSaga forced GoFukakusa to abdicate in favor of Kaneyama. Kaneyama's son was named Crown Prince (later known as Emperor GoUda). GoFukakusa appealed to the shogunal administration in the city of Kamakura and had his own son (later known as Emperor Fushimi) named next in line after GoUda. During the reign of GoUda, GoFukakusa excerted power from the office of Retired Emperor. An agreement was reached by which the next emperors would alternate between descendents of GoFukakusa and descendents of Kameyama.