852 were built between 1935 and 1946 (not all to LMS order), as a freight version of William Stanier's successful Black Five, and the class saw extensive service overseas during and after the Second World War.

LMS freight traction suffered from the adoption of the Midland Railway's small engine policy which had left it with trains double-headed by underpowered 0-6-0s supplemented by disappointing Garratts and Fowler 7F 0-8-0s.

The War Department had 208 8Fs built by Beyer Peacock and North British Locomotive Company and requisitioned 51 more.

25 of these were subsequently transferred to the GWR, still on loan from the WD, but retained their LMS numbers.

All 245 entered BR stock at the start of 1948 and subsequently had their LMS numbers increased by 40000.

[15] These were paid for by the LNER, which had informed the Ministry of War Transport that they were willing to buy up to 100 of these locomotives in the national interest.

[17] The War Department originally ordered 8Fs for service in support of the British Expeditionary Force, but they were not delivered until after the Fall of France.

However, most of them did see wartime military service overseas in Egypt, Palestine, Iran and Italy.

[18][page needed] The British Army's Middle East Forces (MEF) in Egypt received 42 8Fs in 1941-42, with some having been lost at sea en route (246-304, 322, 370, 371, 415, 416, 428, 429, 444 & 445)[19] possibly on the SS Thistlegorm.

The scarcity of water made steam locomotive operations on the WDER difficult, and their smoke also attracted unwanted attention from enemy aircraft, so once American diesels began to arrive from late 1942 the use of 8Fs on the WDER declined.

Following the occupation of Iran in 1941, WD locomotives were required to operate the Persian Corridor supply route, delivering war materials to the Soviet Union via the Trans-Iranian Railway.

After the war they were sold to Ferrovie dello Stato, where they operated as FS Class 737 until the early 1950s.

[29] Twenty-five new WD locomotives were sold to Turkish State Railways (TCDD) in 1941 for diplomatic reasons, but seven of these were lost at sea en route (338, 343-345, 354-356.

With their intended role in France having ceased to exist, early WD 8Fs were loaned to British railway companies in 1940-42, being given temporary numbers in the LMS series.

The other two were transferred to the Cairnryan Military Railway and were scrapped in 1959, ending the WD's use of 8F locomotives.

Despite some having operated in Scotland by the LMS, they were not common on the Scottish Region under BR ownership as the later WD 'Austerity' 2-8-0 and 2-10-0 types were used instead.

48773 had diagonal yellow stripes painted on the cabsides to indicate that it could not run south of Crewe due to it being out of gauge for the new 25 kV AC overhead electrification.

Of the six LMS/BR locomotives that exist, only 48773 was purchased directly from BR for preservation following withdrawal from Rose Grove in July 1968; the remaining five - including 48518 which would later be used as a donor engine - were all rescued from Barry Scrapyard.

Three members of the class have over the years been repatriated to the UK from Turkey, with one later sent to a museum in Israel.

Two of the Turkish based 8F's which were to be repatriated to the UK, no's 45166 & 45170 made an appearance on the Channel 5 TV programme Monster Moves,[42] this episode showed the two engines being moved 850 miles by rail across Turkey from Sivas to İzmir.

In addition, two Turkish Railway (TCDD) locomotives have been preserved in Turkey, and some more remain there in a derelict state.

These have been regular main line performers in recent years with 48773 being withdrawn from operation in 2000.

This practice began under the auspices of British Railways, to denote that locomotives thus treated were able to work fast, vacuum-braked goods services.

Another difference between the British engines and the locos that were exported from Britain is the position of the driver's controls.