 The Yeomanry Cavalry and Imperial Yeomanry were military units in the 18th and 19th centuries.In the U.S. Navy and the U.S. Coast Guard, the enlisted rating of yeoman describes an enlisted service member who performs administrative and clerical work ashore and embarked aboard vessels at sea.They deal with protocol, naval instructions, enlisted evaluations, commissioned officer fitness reports, naval messages, visitors, telephone calls and mail (both conventional and electronic).