In part a learned form of Luke, in part a transferred use of the surname derived from it in the Middle Ages. The Latin form Lucas was often used in the Middle Ages in written documents in place of the spoken vernacular form Luke, hence the common surname. It is also the spelling preferred in the Authorized Version of the New Testament, which has had some influence on its selection as a given name. There has been a sharp rise in its popularity since the turn of the century. Lucas is now also used as an Anglicized form of various Eastern European equivalents (see the cognates listed at Luke).