This article explores the extent to which post-war concerns about Englishness and fears about ‘the enemy within’ shaped understandings of the ‘racecourse wars’ of the 1920s. These conflicts involved mainly metropolitan criminals in various affrays and fights on the streets of London, and on the racecourses of South-East England. The press coverage of the events has been described as akin to a ‘moral panic’ and certainly they provided serious headline fodder during the peaks of 1922 and 1925. Moreover, the key personnel of these ‘wars’, arguably dramatically overwritten by the press, have become signposts in the chronology of twentieth-century British organized crime. This article will draw upon newspaper reports, police autobiography, trial reports, Metropolitan Police records and correspondence with the army to explore concerns about the nature and prevalence of gang crime and forms of inter-personal violence