This most interesting and unusual surname is of Old Scandinavian origin, and is a metathesized form of Crennell, a Manx name from "Mac Reghnaill", meaning "son of Raghnall", itself from the Old Norse "Rognvaldr", composed of "ragin", counsel, and "wald", rule (Ruler of the Gods). This was first introduced into Britain by Scandinavian settlers, and was the name of several kings of the Isle of Man. The surname first appears in its original form in the late 11th Century in medieval Irish Records (see below), while the modern surname appears regularly in Church Registers of the Isle of Man. A. W. Moore in his published work "Manx Names", traces the following development of the surname: MacReynylt (1511); Crenilt (1627); Crellin (1601); and Crennil (1646). Examples of the surname found in Isle of Man Church Registers include: the marriage of John Crellin and Katharine Tyldesley on January 1st 1632, at Marown; the marriage of Daming Jo Crellin and Katharine Tybdisley in October 1662, at Malew; and the christening of Elizabeth, daughter of Thomas Crellin, on May 29th 1669, at Braddan. The first recorded spelling of the family name is shown to be that of Godfrey Mac MicRagnaill, King of Dublin which was dated 1075, in "Manx Names", by A. W. Moore, during the reign of Irish High Kings in Opposition, 1022 - 1166. 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.