 After the First World War cavalry units were mostly converted from horses to either armoured cars or tanks which became known as either mechanized cavalry fulfilling a reconnaissance role, or armoured cavalry serving in the offensive role that seeks to break through the enemy defences.In October 1928, a new era began for the cavalry of the British Army when the 11th Hussars became the first regular cavalry regiment to "mechanize", to change from a horsed cavalry role to a mechanized one, re-equipping with armoured cars previously used by the Royal Tank Corps.Other regiments followed suit; in April 1939, the Royal Armoured Corps was formed to encompass the eighteen mechanized cavalry regiments of the line alongside the eight battalions of the Royal Tank Regiment, but did not include the Household Cavalry.