The War Department (WD) "Austerity" 2-10-0 is a type of heavy freight steam locomotive that was introduced during the Second World War in 1943. The Austerity 2-10-0 was based on the Austerity 2-8-0 and was designed to have interchangeable parts by R.A. Riddles. It had the same power output as the 2-8-0 but a lighter axle load, making it suitable for secondary lines.

Two batches were built by the North British Locomotive Company, the first batch of 100 introduced in 1943/1944 and the second batch of 50 in 1945. 20 of the first batch were sent to the Middle East. During running-in they worked in Britain, but their length made them unsuitable. Most saw service with the British Army in France after D-Day in the drive towards the Siegfried Line.

After the war, BR bought twenty-five locomotives. These were initially numbered 73774-73798 but later re-numbered 90750-74. They were mostly operated by BR's Scottish Region on heavy freight trains and were all withdrawn between 1961 and 1962.

LMR 600 Gordon has survived and has been steamed on the Severn Valley Railway. Two more have been repatriated from Greece. One has been numbered 90775, one higher than the last BR engine, and is operational on North Norfolk Railway where it has now been renamed The Royal Norfolk Regiment. The other is WD No. (7)3672 which has been named Dame Vera Lynn. The loco is currently being overhaul at Grosmont on the NYMR. The 4th one in preservation WD 73755 (NS 5085) survives in the Dutch Railway Museum (Nederlands Spoorwegmuseum) in Utrecht. It carries the nameplate Longmoor, after the Royal Engineers base at Longmoor, with the coat of arms of the Royal Engineers above.

Four locomotives remain in various states in Greece with Λβ962 and Λβ964 operating mainline tours on the Drama to Xanthi line. 2 other locomotives remain in poor states stored awaiting further use. None of the 4 are included here.