This interesting name is of Medieval English origin and is locational from a so called "lost" village, which is named from the Old English pre 7th Century words "caerse, cerse", (water) cress and "lacu", stream or lake, thus a stream where water-cress grew. The phenomenon of the "lost" village was a result of enforced land clearance in the 12th and 13th centuries, at the height of the wool industry, to make way for sheep pasture. It is estimated that there are between seven and ten thousand such places that have disappeared from British maps. During the Middle Ages when people left their birthplace to seek work elsewhere they would often adopt the placename as a means of identification, thus resulting in a wide dispersal of the name. The modern surname can be found as Carslake, Caslake, Keslake, Kerslake and Karslake. The marriage of William Keslake and Elizabeth Stephens was recorded on May 7th 1626 at Barnstaple, in Devonshire. The first recorded spelling of the family name is shown to be that of Ranulph de Carselak, which was dated 1279, in the "Assize Rolls of Somerset", during the reign of King Edward 1, known as "The Hammer of the Scots", 1272 - 1307. 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.