1590s, "on horseback," past-participle adjective from mount (v.). From 1690s as "set up for display."
Entries linking to mounted
mount v.
c. 1300, mounten, "to get up on a horse;" mid-14c., "to rise up, rise in amount, ascend; fly," from Old French monter "to go up, ascend, climb, mount," from Vulgar Latin *montare, from Latin mons (genitive montis) "mountain" (from PIE root *men- (2) "to project"). The transitive meaning "to set or place in position" first recorded 1530s. Sense of "to get up on for purposes of copulation" is from 1590s. Meaning "prepare for presentation or exhibition" is by 1712. Military meaning "set up or post for defense" is by 1706; to mount an attack is by 1943. Related: Mounted; mounting.
Mountie n.
1914, member of the Royal Canadian (originally North-west) Mounted Police, formed 1873 to keep order in the former Hudson's Bay Company lands. Also see -ie.