Reformed in 1920 in the Territorial Army (TA) as the 48th (South Midland) Infantry Division, it saw active service in the Second World War with the British Expeditionary Force (BEF) in Belgium and France before being evacuated from Dunkirk to the United Kingdom.

In 1901, following lessons learned from the Second Boer War and diplomatic clashes with the growing German Empire, the United Kingdom sought to reform the British Army so it would be able to engage in European affairs if required.

[4] Haldane envisioned that the territorials would take over the defence of the country against what was perceived as a very real threat of invasion, which would allow the regular army to be deployed aboard.

Six months following mobilisation, during which time the troops would have come up to an acceptable training standard, Haldane was confident that up to a quarter of the men would opt to go and fight abroad.

[15] In March 1915, with the threat of a German invasion having subsided, the South Midland Division was dispatched to France with the territorials who had volunteered for overseas service.

[17] The members of the division who did not, or were not able to, volunteer for overseas service, were transferred to newly created second line units intended for home defence.

These second line units were eventually formed into the 61st (2nd South Midland) Division and, following the passing of the Military Service Act 1916, deployed to France in February 1916.

However, as the 1920s and 1930s wore on, the British Government prioritised funding for the regular army over the territorials, allowing recruitment and equipment levels to languish.

[26] Baron Templemore, as part of a House of Lords debate on the Territorial Army, stated that the division - on 1 October 1924 - mustered 338 officers and 7,721 other ranks.

[27] Historian David French highlights that "by April 1937 the Territorial Army had reached less than 80 per cent of its shrunken peacetime establishment" and "Its value as an immediate reserve was, therefore, limited.

"[26] Edward Smalley comments that "48th Divisional Signals operated on an improvised organizational structure" for most of the 1930s, due to being below 50 per cent strength.

[32] However, the unexpected surrender of Belgian forces on 27 May 1940 led to a gap appearing between 48th Division in action around Saint-Omer and the coast at Nieuwpoort.

Until II Corps could arrive to plug this gap, Lawson was responsible for what the Official History calls 'the most dangerously exposed part of the bridgehead'.

At 11.00 on 28 May, advanced German troops reached the canal line, but Lawson seized on the Territorial gunners of the 53rd (London) Medium Regiment, RA who were marching towards Dunkirk having fired off all their ammunition and destroyed their guns.

Together with detachments of Regular gunners from both the 2nd Medium and 1st Heavy Anti-Aircraft Regiments, and sappers from 7th Field Company, Royal Engineers, they fought as infantry to hold the line.

They came under heavy mortar and machine gun fire, and the Germans seized a bridgehead at Nieuwpoort, but all subsequent attacks that day were repulsed.

[44][45] During November 1941, the division was placed on the "Lower Establishment" and assigned to I Corps District, commanded by Lieutenant General Henry Willcox.

Over the following six months, up to 75 per cent of these men were deployed to reinforce the 21st Army Group, following the completion of their training and having met the required fitness levels.