The Oxford Publishing Company (OPC) is thought to have begun its existence in the mid-20th century as an imprint of Cassell & Co. In addition to publishing non-fiction books on railway subjects, OPC undertook a joint venture with British Railways in the 1970s to provide copies of the latter's locomotive, carriage & wagon, architectural and track plan engineering drawings to railway enthusiasts. The company also produced lists of railway postcards and provided railway photographs to the public.

In 1987 OPC was bought by Haynes Publishing and was subsequently acquired by Ian Allan, a long-established titan of railway publishing, in 1998. The OPC imprint was sold to Crecy Publishing when Ian Allan moved out of the railway publishing market in 2017.