This surname is of Anglo-Saxon, Old Norse origin, and is a dialectal variant of the locational name Osleston, from the place in Derbyshire, deriving from the Old Norse personal name "Oslaf", meaning "god-love", plus the Olde English pre 7th Century "tun" homestead, farm, hence "Oslaf's tun". The placename is recorded as "Oslavestune" in the Domesday Book of 1086, and as "Oslaueston" in the Derbyshire Charters in the 13th Century. During the Middle Ages when it was increasingly common for people to migrate from their birthplace to seek work further afield, the custom developed that they would adopt the placename as a means of identification. Variations in the spelling of the surname include Asselton, Ossulton and Oselton. Yorkshire Church Records list the christenings of Ann, daughter of John and Ann Asselton, on the 9th April 1704 at Stainton in Cleveland and of Mary, daughter of Thomas and Elizabeth Osselton, on the 7th April 1803, in Catterick. Robert, son of John and Jane Osselton, was christened on the 7th December 1845 at St. John's, Stanwick. The first recorded spelling of the family name is shown to be that of Thomas Asselton, which was dated 7th December 1602, witness to the christening of his daughter Jaine, in Stainton, Cleveland, Yorkshire, 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.