Recorded in a number of spellings including Radsdale, Ridesdale, Ridsdale, Ridsdell, Ridsdill, Rudsdale, Rudsdell and possibly others, this is an English locational surname. It originates from Redesdale, a village in the county of Northumberland, north east of the town of Bellingham. First recorded in the year 1075, the place is so named from it's position in the valley of the river Rede. The river name literally means 'red', a reference to the iron stone in the area, which sometimes gives the river a red appearance. The second element is from the Norse-Viking word 'dael' meaning a deep valley. Locational surnames were ones usually given to people after they left their origin homes to move somewhere else. This name for instance is rarely found in Northumberland, but relatively popular in the London area. Recordings of the surname occur in the London church registers from Elizabethan times and examples include John Ridesdale and Juliana who were married at Saint Botolph's Bishopsgate, on February 12th 1604, Charles Rudsdale who was christened at St Clements Danes on January 13th 1734, and in the north, William Ridsdale who married Sophia Peterkin at Manchester Cathedral, Lancashire, on February 14th 1774. One of the earliest recordings is that of Thomas Rydsdale, which was dated April 19th 1568 at St. Andrew's Undershaft, in the city of London. Throughout the centuries, surnames in every country have continued to "develop" often leading to astonishing variants of the original spelling.