This interesting surname of Scottish origin is a locational name from the lands of Glencrosh near Monlaive, old spellings of which are Glencros, Glencrosche, Glencrash, and Glencorse, derives from the Gaelic Gleann" meaning "Glen" plus "cros" "cross". The surname dates back to the early 14th Century, (see below). Further recordings include one John Glencors and James Glencors, followers of the earl of Cassilis who were respited for murder in 1526, "The Register of the Privy Seas of Scotland", and Margaret Glencorss who was retoured heir of Alexander Glencorss "de eodam", her grandfather, in 1609, "Retours, Dunfriesshire). Janet, daughter of Thomas and Elizabeth Glencross, was christened on March 6th 1802, at Edinburgh, and John Glencross married Helen White in Dalkeith, London, on September 18th 1807. The first recorded spelling of the family name is shown to be that of Johannes, clericus, de Glenkrosch, witnessed the sale of a tenement in Gouertun, which was dated 1317, in the "Registrum S. Marie de Neutbotle, Edinburgh", during the reign of King Edward 11, of "Caernafon", 1307 - 1327. 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.