Bojutsu as a system developedin the late Kamakurs period (1192-1333) or the early Muromachi period (1338-1598). The use of the bo heightened in Okinawa during the Satsuma clan's occupation (17th-18th centuries). Becoming popular with other implements including the sai, the kama, the tonfa, and the nunchaku, it became one of the five systemized weapons of early karate.