This interesting surname is of early medieval English origin, and is from an occupational name for an inn-keeper, derived from the Middle English (1200 - 1500) "(h)osteler", similar to the Old French "(h)ostelier", an agent derivative of "hostel, hostal", a house which could accommodate guests in separate rooms. The term was first applied to the secular officer in a monastery who was responsible for the lodging of visitor, but it was later extended to keepers of commercial hostelries, and this is probably the usual sense of the surname. The more restricted modern English sense "groom", is also a possible source. The surname development since 1190 (see below) includes the following: Robert le Osteler (1204, Staffordshire), Robert le Hostler (1275, Norfolk) and Henry Husteler (1301, Yorkshire). The modern surname can be found as Ostler, Oastler, Osler, Host(el)ler, Hustler and Horsler. Among the recordings in London are the marriages of Henry Ostler and Dulcey Butt on August 16th 1686 at All Hallows, London Wall, and of Francis Ostler and Elizabeth Cooke on July 15th 1722 at St. Martin-in-the-Fields, Westminster. The first recorded spelling of the family name is shown to be that of William Hostiler, which was dated 1190, The Eynsham Cartulary of Oxford, during the reign of King Richard 1, "The Lionheart", 1189 - 1199. 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.