This most interesting and unusual surname is of early medieval English origin, and is a topographical or occupational name for someone who lived or worked at a stables, a colt-house or colt-keeper, from the early modern English word "coulthus", which is a compound of "co(u)lt", an Olde English word for a young ass, or young horse, a colt, and "hus", the Olde English word for house. The name itself is widespread in the Yorkshire region, and was first recorded there in the late 16th Century (see below). The Church Registers of Yorkshire record the following early entries of the surname: the christening of Robert, son of Robertus Cowltus, on February 26th 1575 at Hackness; the marriage of Robert Coultas and Anna Snipe on July 22nd 1576, also at Hackness; while Isabel Coultas married Richard Markson on October 26th 1621 at Wintringham. The first recording of the surname in London Church Registers is the christening of Margaritt Coltis, daughter of William Coltis, on May 11th 1576 at St. Botolph without Aldgate. The first recorded spelling of the family name is shown to be that of William Cowthus, which was dated 1562, in the "Register of the Freemen of the City of York", during the reign of Queen Elizabeth 1, known as "Good Queen Bess", 1558 - 1603. 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.