1) A case or bag which would hold clothing and other necessaries; used by those riding on horseback.
1610 one port mantć, Kirkstall
1632 A Port Mantua 4s, Sprotbrough. ‘Portmantle’ was a regional spelling: 1700 One port Mantle 2s, Elland
1721 had his portmantle cut from behind his horse, with a buckskin and above twenty pair of shoes in it ... port mantle or cloak bagg, West Riding.