This book fills a significant gap in the historiography of British military thought, doctrine and practice for the First World War (1914-18) and the generation beforehand, including the Boer War (1899-1902). It investigates a major doctrinal controversy: what the role and tactics of horsed soldiers were to be in the face of increasing firepower and demands placed upon them by the expansion of mass armies. Contrary to widely held modern belief, the doctrine developed proved quite successful in dealing with the conditions that they faced on the battlefield.