56th (Cornwall) Heavy Anti-Aircraft Regiment, Royal Artillery was a volunteer air defence regiment of Britain's Territorial Army (TA). Originally raised in 1920 as a medium artillery regiment, it was converted to the anti-aircraft role in 1932. During the Second World War, it was employed in Home Defence, in Iceland and then in India, where it was temporarily converted back to medium artillery. Postwar, it reverted to air defence until disbandment in 1955. Origin With the reorganisation of the Territorial Force (TF) into the new TA in 1920, a new medium artillery unit was formed, under the title 7th (Cornwall and Warwickshire) Medium Brigade, Royal Garrison Artillery, renumbered 51st the following year. It initially had its headquarters at Truro, Cornwall, and comprised three new Cornish batteries based at Padstow, Par and Penzance, and one existing heavy battery from Birmingham, Warwickshire. 51st (Cornwall and Warwickshire) Medium Brigade There had been Artillery Volunteer Corps (AVCs) at Padstow and Par since 1859, and at Penzance since 1877, and these had later formed part of the 1st Cornwall (Duke of Cornwall's) Artillery Volunteers. This unit had defended the Cornish ports throughout the World War I, but in the postwar reorganisation it became a Coast Artillery brigade based at Falmouth, and new batteries were raised at Padstow, Par and Penzance for the 51st Medium Brigade. The other battery had originally been raised in 1908 at Saltley, Birmingham, as the South Midland (Warwickshire) Royal Garrison Artillery, which provided the Heavy battery of the 48th (South Midland) Division of the TF. It had served on the Western Front during World War I. With minor changes in title over succeeding years, the new unit was organised as follows: 51st (Cornwall and Warwickshire) Medium Brigade, Royal Garrison Artillery HQ St Austell 201st (Cornwall) Medium Battery, RA, Padstow 202nd (Cornwall) Medium Battery, RA (Howitzer), Par 203rd (Cornwall) Medium Battery, RA, Penzance 204th (Warwickshire) Medium Battery, RA, Saltley 56th (Cornwall) Anti-Aircraft Regiment In 1932, as part of the increase in air defence for the United Kingdom, 51st Medium Brigade was converted into 56th (Cornwall) Anti-Aircraft Brigade. The HQ was at Falmouth and the three Cornish batteries (201, 202 and 203) were converted to the new role. In place of the Birmingham battery, the unit received 165th Battery at Redruth, which had formerly been part of the Cornwall Coast Brigade (former 1st Cornwall (Duke of Cornwall's), see above). The regiment formed part of