This interesting and unusual surname is of Old Scandinavian origin, and is a patronymic form of "Kel, Kil", itself a diminutive from the Old Norse personal name "Ketill", a short form of various compound names ending in "-ketill, -kjell", cauldron, with the patronymic suffix "-son, -sen"; hence, "son of Kel". In Norway and Denmark this has given the patronymic surnames Ketels(sen) and Kjeldsen, while the personal name has led to the formation of the surnames Kettle, Kettel, Ketill, Kitell, Kettles and Kettelson in England. Pre 7th Century Anglo-Saxon and Norse baptismal names were usually distinctive compounds whose elements were often associated with the Gods of Fire, Water and War. Scandinavian patronymic surnames are unusual in that up until recent times, that is from the mid 17th Century onwards, people were given their father's christian name with the patronymic suffix "-son (sen)". This is shown in Swedish Church Registers: for example, Niels Kieldsen, son of Kield Colbiornsen, was christened on February 4th 1716, at Sorum, Akershus, Norway. William Kelson was christened on April 30th 1689, at Sowerby by Thirsk, Yorkshire. Other early examples include the birth of Margaret Kjeldsen at Nes, Akershus, Norway, in 1645, and the marriage of Daniel Keilsen to Magnild Areutsdr at Oyestad, Aust-Agder, Sweden, on June 20th 1723. The first recorded spelling of the family name is shown to be that of Robert Cilson, which was dated October 8th 1555, marriage to Maude Harrison, at Oswaldkirk, Yorkshire, during the reign of Queen Mary, known as "Bloody Mary", 1553 - 1558. 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.