Thieves' cant

Thieves' cant or rogues' cant, also known as peddler's French, was a secret language (a cant or cryptolect) which was formerly used by thieves, beggars and hustlers of various kinds in Great Britain and to a lesser extent in other English-speaking countries. The classic, colourful argot is now mostly obsolete, and is largely relegated to the realm of literature and fantasy role-playing, although individual terms continue to be used in the criminal subcultures of both Britain and the United States. Its South German and Swiss equivalent is the Rotwelsch and Serbo-Croatian equivalent is Šatrovački.

It was claimed by Samuel Rid that thieves' cant was devised around 1530 “to the end that their , and might not so easily be perceived and known”, by Cock Lorel and the King of the Gypsies at The Devil's Arse, a cave in Derbyshire. It does seem to have originated in this period but the story is almost certainly a myth.

Cant was a common feature of rogue literature of the Elizabethan period in England, in both pamphlets and Elizabethan theatre. Thomas Harman, who claimed to be a justice of the peace, included examples in his Caveat for Common Cursitors (1566). He claimed that he collected his information from vagabonds he interrogated at his home in Essex. He also called it “pedlars’ French” or “pelting speech”, and said he was told that it had been invented as a secret language some 30 years earlier. The earliest records of canting words are included in The Highway to the Spitalfields by Robert Copland c.1536. Copland and Harman were used as sources by later writers. A spate of rogue literature started in 1591 with Robert Greene's series of five pamphlets on and coney-catching. These were continued by other writers, including Thomas Middleton, in The Black Book and Thomas Dekker, in The Bellman of London (1608), Lantern and Candlelight (1608) and O per se O (1612). Cant was included together with descriptions of the social structure of beggars, the techniques of thieves including coney-catching, gull-groping and gaming tricks, and the descriptions of low life of the kind which have always been popular in literature. Many of these pamphlets borrowed from earlier works, sometimes wholesale.

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