This interesting name is of English locational origin from a place thus called in the North Riding of Yorkshire, recorded variously as Selungesbi and Eslingesbi in the Domesday Book of 1086, the first element of the placename is the old Norse personal byname Sleng(r), "Idle", plus the old Norse personal byname Sleng(r), "Idle", plus the old Norse "by", a farm or settlement; hence, "Sleng's settlement". The surname was first recorded in the early 13th Century, (see below). Other early recordings include: Richardus de Slyngesby and Willelmus de Slenggesby, the 1379 "Poll Tax Returns of Yorkshire", and John de Slengesby, "Wayder", "The Register of the Freemen of York City", (1405). In 1577 one, Charles Slingesbey of Yorkshire was entered in "The Oxford University Register". Notable namebearers were Sir Henry Slingsby (1602 - 1658), royalist; created Novia Scotia baronet, 1638; executed on Tower Hill during the Commonwealth. His cousin Sir Robert Slingsby, comptroller of the navy, 1660 - 1661, was created a baronet at Restoration. The first recorded spelling of the family name is shown to be that of Roger de Slingesby, which was dated 1219, "The Curia Regis Rolls of Yorkshire", during the reign of King Henry 111, "The Frenchman", 1216 - 1272. 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.