Chapman code

Chapman codes are a set of 3-letter codes used in genealogy to identify the administrative divisions in the United Kingdom, Ireland, the Isle of Man and the Channel Islands.

They were created by the historian, Dr. Colin R Chapman, in the late 1970s, and as intended, provide a widely used shorthand in genealogy which follows the common practice of describing areas in terms of the counties existing in the 19th and 20th centuries.

Chapman codes have no mapping, postal or administrative use. They can however be useful for disambiguation by postal services where a full county name or traditional abbreviation is not supplied after a place name which has more than one occurrence, a particular problem where these are post towns such as Richmond.

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