Pirates who held no allegiance to any state, called Wako (Japanese pirates), were active during the Muromachi period; the term "early Wako" is used to describe such pirates in the fourteenth century, while "later Wako" refers to Wako of the fifteenth century.
室町時代には倭寇と呼ばれる無国籍海上勢力が活動し、14世紀の倭寇は前期倭寇、15世紀の倭寇は後期倭寇と呼ばれる。