Double barrelled surnames are the (usually) Victorian equivalent of the pre 7th Century Old English compound personal names. These were comprised of two elements, which had an individual meaning, but not when conjoined. In this case, "Milton" is a locational name from one of the many villages so called. There are two possible meanings, both Old English, either "Middel-Tun", the farm in the middle (of the estate), or "Mylen-Tun" which means "Mill Farm". In the case of "White", the name can be a nickname (Anglo-Saxon) for a person with fair hair (hwita), or it may be an Anglicization of the French (Huguenot) "blanc", with the same meaning, or it can be job descriptive for a "whitesmith", one who works with tin. This latter explanation is probably found in Walter Le Whyte in 1284, London Pipe Rolls. The first recorded spelling of the family name is shown to be that of Boia on Mylatune, which was dated 972 a.d., The register of Old English Location names during the reign of King Edgar, "The Saxon", 959 - 975 a.d. 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.