This name is of English origin, and is found particularly in Yorkshire where surnames from the points of the compass were common. 'Westerman' is a topographical or regional surname meaning 'one from the west', someone who lived to the west of a settlement, or who had migrated from a place further to the west. The derivation is from the middle English 'west' west, and 'mann', - man. An early recording of a bearer of the name is of one Ricahrd Westman who married Fayth Bagnoll, on the 25th October 1581, at St. James, Clerkenwell, London. The first recorded spelling of the family name is shown to be that of Johannes Westeman. which was dated 1379, The Poll Tax Records Of Yorkshire. during the reign of King Richard II, Richard of Bordeaux, 1377 - 1399. Surnames became necessary when governments introduced personal taxation. In England this was known as Poll Tax. Throughout the centuries, surnames in every country have continued to "develop" often leading to astonishing variants of the original spelling.