This is a locational name which is of Ancient British (pre Roman) origin and derives from Kalder, Kelder, Keldin or Caldre, the early 13th century spellings of the various rivers found in Yorkshire, Lancashire and Monmouth, now all spelt Calder. The name translates 'the stream of violent water' (called-dubro) and the name development has included, (1711) John Calder (deceased), St. Dionis, London, whilst the variant spelling of Chalder - Robert Chalder, baptised at St. Andrews, Holborn, London, is first recorded in 1699. The first recorded spelling of the family name is shown to be that of Thomas de Calder. which was dated 1246 The Pipe Rolls of Lancashire. during the reign of King Henry III 'The Frenchman' 1216-1272. 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.