Recorded in a number of spellings including Coldtart, Coltart, Colthard, Colthart, Coltherd, Colthert, Coulthard, Coulthart, and possibly others, as shown below, this is a medieval Anglo-Scottish surname. It has at least two possible origins. It may be French, and locational from a place called 'Coudhart', a village in the department of Orne in Normandy. Many knights who served William, Duke of Normandy, in his Coinquest of England in 1066, were later to serve the various kings of Scotland, where they were rewarded by being granted lands. Secondly it may originally have been English and occupational. If so it derives from the pre 7th century phrase 'colt hierde', meaning a herdsman, one who was specifically trained to look after young horses. The surname is first recorded in Yorkshire as shown below, and later at Berwick on the Anglo - Scottish border at the beginning of the 14th century. It is said that some nameholders were members of the (in)famous Border Reivers who 'reigned' over the Border Country for nearly one thousand years causing mayhem and destruction . Early examples of recordings include Alan Colthird, a witness at the sealing of an inquest with regard to fishing rights on the River Tweed in 1467, whilst no less than sixteen nameholders in about sixteen different spellings appear in the Commissariot Record of the county of Lanark in 1686. The first recorded spelling of the family name is believed to be that of Peter Coltehird. This was was dated 1301, in the SubsidyTax Rolls of the county of Yorkshire, during the reign of King Edward Ist of England 1272-1307. Throughout the centuries, surnames in every country have continued to "develop" often leading to astonishing variants of the original spelling.