Recorded in several spellings including Hadden, Haden, Haddon, Haddin and Howden, this is an English or Scottish surname. In either case it is locational and territorial. In England the name derives from any of the four places called Haddon in Derbyshire, Dorset, Huntingdonshire and Northamptonshire, recorded variously as Hadun and Hadone in the Domesday Book of 1086 for the above counties. The places were so named from the Olde English pre 7th Century word "hoeth", meaning "heathland" plus "dun", a hill; hence, the "heather-covered hill". The surname first appears on record in England in the mid 12th century and early recordings include: Philip de Haddon of Somerset in 1376, and Jordan de Haddone of Huntingdonshire in 1273. In Scotland the name derives from the old barony of Hadden, in the county of Roxburgh. The earliest recording from this source was that of Ulkillus de Hauden, a grant witness in Kelso, circa 1165 - 1171. In 1514, Silverster Hadden, of Kellor, witnessed a retour of service at Forfar. An interesting namebearer, recorded in the "Dictionary of National Biography", was Walter Haddon (1516 - 1572), regius professor of Civil Law, 1551, who was named master of request on accession of Elizabeth 1st in 1558. The first recorded spelling of the family name is shown to be that of Ailwin de Haddun, which was dated 1159, in the Pipe Rolls of London, during the reign of King Henry 11nd of England, 1154 - 1189. Throughout the centuries, surnames in every country have continued to "develop" often leading to astonishing variants of the original spelling.