This is an anglicized form of the Olde Gaelic Mac Liaig(h). The Gaelic prefix "mac" means "son of", plus the personal byname Liaigh meaning "physician" or "healer". The surname is first recorded in the early 11th Century, (see below). One, Gilla MacLiag is mentioned in A.W. Moore's, "Manx Names" under the date 1173. The forms Claige, Claque and Clague, appearing in Church Registers of the Isle of Man from 1601 onwards, result from the fusion of the "c" in "mac" with the personal name Liag, later written as Laque and Lague. On February 27th 1624 a daughter was born to Robert Claque of Marown, and on July 4th 1698 Mary Clague, an infant, was christened in Braddan. The marriage of Alice Clague and John Cubon was recorded in Braddan on July 4th 1710. Clegg, a further anglicized form of the name emerged in the 19th Century. The first recorded spelling of the family name is shown to be that of MacLiag, which was dated 1014, in the Early Records of the Isle of Man, during the reign of King Ethelred, known as the Unready of England, 978 - 1016. 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.