Military of Ryukyu

300px|thumb|Walls of Shuri Castle often refers to castles or fortresses in the Ryukyu Islands that feature stone walls. However, the origin and essence of remain controversial. In the archaeology of the Ryukyu Islands, the Gusuku period refers to an archaeological epoch of the Okinawa Islands that follows the shell-mound period and precedes the Sanzan period, when most are thought to have been built. Many and related cultural remains on Okinawa Island have been listed by UNESCO as World Heritage Sites under the title Gusuku Sites and Related Properties of the Kingdom of Ryukyu.

invasion of the Ryukyu Kingdom by the Satsuma Domain, resulting in the former’s being reduced to a vassal state of the latter