Ashigaru
Ashigaru is a type of Japanese soldier that began during the Heian Period (794-1185). Their origin is serving as bodyguards to government officials during this period.  They became more active over hundreds of years and ended up serving as foot-soldiers for samurai and shogun.  Ashigaru became masterless warriors after the beginning of the Edo Period (1603-1868). After the Edo Period, many became police.