This name is of Anglo-Saxon origin, and is locational from a place in Kent called Hadlow, or from Hadlow (Down) in Sussex. The former, recorded as "Haslow" in the Domesday Book of 1086, and as "Hadlo" in the 1241 Episcopal Registers of Kent, is so called from the Olde English pre 7th Century, "hath", a side form of "haeth", meaning heathland or heather, plus "hlaw", a hill or burial mound; hence, "heather-covered hill". The latter, appearing as "Hadleg" in the 1254 Patent Rolls of Sussex, and as "Haddele(g)h" in the "Place Names of Sussex" (1279), derives its name from the Olde English "haeth", heather, plus "leah", a wood or clearing. The surname was first recorded in the latter part of the 13th Century (see below). Recordings from English Church Registers include: the christening of William Hadlow, an infant, on January 6th 1546, at Offham, Kent; the marriage of Giles Hadlow and Annes Eton on September 22nd 1566, at Chevening, Kent; and the christening of William Hadlow at Grinstead, Sussex, on April 17th 1586. The first recorded spelling of the family name is shown to be that of John de Hadlo, which was dated 1273, in the "Hundred Rolls of Kent", during the reign of King Edward 1, known as "The Hammer of the Scots", 1272 - 1307. 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.