This is a list of Royal Northumberland Fusiliers battalions in World War II. At the outbreak of the Second World War in September 1939 the Royal Northumberland Fusiliers, a fusilier infantry regiment of the British Army, consisted of seven battalions. A further three were raised during the war. Prior to the war, the regiment was one of a number that been selected to transition from an infantry role to a support role and be equipped with the Vickers machine gun. While most battalions served as divisional machine gun or support battalions, several undertook different roles: motorcycle, searchlight, tank, reconnaissance, regular infantry, and deception units. The regiment saw action with the British Expeditionary Force (BEF) during the Battle of France and Dunkirk, defended the United Kingdom, fought in the North African Campaign, took part in the Battle of Singapore, fought in the Italian Campaign, and operated with the 21st Army Group in the North-West Europe Campaign of 1944–45, operating on the Western Front.

Inter-war years In November 1919, following the end of the First World War, the war-raised battalions of the Northumberland Fusiliers were disbanded. The single exception was the 3rd (Special Reserve) Battalion. While its personal were transferred to the Regular Army 1st Battalion on 12 July 1919 disembodied on 29 July, it was not formally disbanded until April 1953.

On 7 February 1920, following the establishment of the Territorial Army (T.A.), the 1st Line Territorial Force battalions of the regiment were reconstituted. The battalions were grouped together, to once again form the Northumberland Brigade, which was part of the Northumbrian Division. During the interwar period, the make-up of the regiment was as follows: 1st Battalion 2nd Battalion 3rd Battalion (Militia) suspended animation 4th Battalion (T.A.) 5th Battalion (T.A.) 6th Battalion (T.A.) 7th Battalion (T.A.)

In June 1935, as part of H.M. King George V's silver jubilee, the regiment was accorded royal status in recognition for their service during the First World War. They would henceforth be known as the Royal Northumberland Fusiliers.

In 1922, the Machine Gun Corps (MGC) was disbanded in order to save money. Following which, Vickers machine guns were organised into Machine Gun Platoons (later, Machine Gun Companies) in each infantry battalion. In 1936, this decision was reversed and the heavy machine guns were, once again, to be concentrated in specialised Divisional (Machine Gun) or Divisional (Support) Battalions. Rather than resurrecting the MGC, a number of infantry regiments were converted to take on the role. The Royal Northumberland Fusiliers was one of four regiments selected for conversion.

The needs of modern mechanized warfare had a significant effect on the regiment's T.A. battalions. The Northumbrian Division was reorganized as a Motor Division, which saw a reduction from three to two brigades (but the addition of a motorcycle battalion) and the Northumberland Brigade was broken up. On 1 November 1938, the role of several battalions were changed. The 4th Battalion was converted to a motorcycle battalion, and assigned to 50th Division The 5th Battalion became a searchlight battalion, styled as 5th Battalion, The Royal Northumberland Fusiliers (53rd Searchlight Regiment), and assigned to the 30th (Northumbrian) Anti-Aircraft Brigade. The 6th Battalion was converted to an armoured role and transferred to the Royal Tank Corps as its 43rd Battalion (6th (City) Battalion, The Royal Northumberland Fusiliers). The 7th Battalion was converted to a machine gun battalion in Northumbrian Area, Northern Command

By 1939, it became clear that a new major war was likely to break out. The War Office ordered the doubling of the T.A., with each unit forming a duplicate. The 4th and 7th Battalions formed duplicates: the 8th and 9th Battalions. On the eve of the Second World War, the Royal Northumberland Fusiliers consisted of: 1st Battalion (MG) 2nd Battalion (MG) 4th Battalion (T.A.) (motorcycle) 5th Battalion (T.A.) (53rd Searchlight Regiment) 7th Battalion (T.A.) (MG) 8th Battalion (T.A.) (motorcycle) 9th Battalion (T.A.) (MG)

Second World War

1st Battalion At the outbreak of the Second World War, the 1st Battalion was a machine gun unit assigned to the 18th Infantry Brigade as part of the British Troops in Egypt. It was stationed at Abbassia, Cairo but was just leaving for Mersa Matruh in the Western Desert. By the end of the month, it was attached to the 7th Infantry Division and was still attached when the division was designated as 6th Infantry Division on 3 November 1939; the battalion remained with it until April 1940.

From April to December 1940, the battalion was attached to the 4th Indian Infantry Division and served in Operation Compass which saw the Italians expelled from Egypt and the capture of Sidi Barrani. Thereafter, the division departed for East Africa without the battalion. From January 1941, it was assigned to XIII Corps and from August to December 1941 it was in Tobruk Fortress. It then came under the command of the Eighth Army until the end of the North African Campaign. Its most notable action was in the Battle of El Alamein when it operated as separate companies among the units of I Corps: HQ attached to 8th Armoured Division W Company attached to 131st Lorried Infantry Brigade, 10th Armoured Division X Company attached to 2nd Armoured Brigade, 1st Armoured Division Y Company reforming Z Company attached to "Hammerforce", 1st Armoured Division

On 19 September 1943, the battalion moved to Syria where it joined the 10th Indian Infantry Division and remained with it for the rest of the war. In March 1944, the battalion transited Palestine and Egypt and shipped to Italy, landing at Taranto on 28 March; it remained on the Italian Front for the rest of the Second World War. The battalion saw action on the Gothic Line and in the 1945 Spring offensive. During the war Captain James Jackman was posthumously awarded the Victoria Cross.

2nd Battalion At the outbreak of the war, the 2nd Battalion, Royal Northumberland Fusiliers was stationed in Dover, Kent, and attached as the machine gun unit to the Colchester based 4th Infantry Division. It joined the British Expeditionary Force (BEF) in France in October 1939 and served there until June 1940. Although organized as a divisional machine gun battalion, it was attached to General Headquarters (GHQ) and was assigned to divisions as required.

It joined Home Forces on its return from Dunkirk and on 11 November 1941 it rejoined the 4th Division as its machine gun battalion until 20 May 1942 when it was posted back to Home Forces. On 3 July 1943, it joined the 46th Infantry Division in North Africa as a support battalion. It moved to Italy with the division taking part in the Salerno landings, capture of Naples, Volturno Crossing and Mont Camino. On 10 March 1944, it left the 46th Division and once again joined the 4th Division. It was reconfigured as a machine gun battalion on 7 June 1944 and remained with the division for the rest of the war. It fought at Cassino II, Trasimene Line, Arezzo, Advance to Florence and Rimini Line. In December 1944, it moved with the division to Greece where it remained until the end of the war.

4th Battalion The 4th Battalion was converted to a motorcycle battalion in 1938, and was assigned to the 50th (Northumbrian) Infantry Division (then organised as a Motor Division) on the outbreak of the war. It served with the division in France and Belgium from January to June 1940. It took part in the action on the Ypres-Comines Canal.

After returning from Dunkirk, the battalion came under command of Home Forces until April 1941; on 30 April 1941 it was transferred to the Reconnaissance Corps and redesignated as 50th Battalion, Reconnaissance Corps, and it rejoined 50th Division. It was then sent to North Africa with the division in June 1941, with a short stay in Cyprus from July to November 1941 and in Iraq from November to December 1941. Much of the time, 50 Recce was attached to the 150th Infantry Brigade in keeping with the then current tactical organisation of brigade groups in the British Army in the Mediterranean and Middle East. From February to June 1942 it was assigned to the 22nd Armoured Brigade.

In June 1942, it returned to the United Kingdom and was in the Home Forces once again. On 6 June 1942 it became 50th Regiment, Reconnaissance Corps and in March 1943 reverted to the Royal Northumberland Fusiliers as the 4th Battalion. On 25 April 1944, the battalion was suspended; its personnel formed three independent machine gun companies for the British armoured divisions of the 21st Army Group: 1st Independent Machine Gun Company assigned to the Guards Armoured Division 2nd Independent Machine Gun Company assigned to the 11th Armoured Division 3rd Independent Machine Gun Company assigned to the 7th Armoured Division All three served throughout the North-West Europe Campaign. They variously saw action at Odon, Bourguébus Ridge, Mont Pinçon, The Nederrijn, The Rhineland, and The Rhine.

5th Battalion (53rd Searchlight Regiment) Note: Although the 5th Battalion spent most of the war as part of the Royal Artillery, its record is included here for completeness.

The 5th Battalion was converted to a searchlight battalion on 1 November 1938 as 5th Battalion, The Royal Northumberland Fusiliers (53rd Searchlight Regiment). At the outbreak of the war, it was assigned to 30th (Northumbrian) Anti-Aircraft Brigade, 7th Anti-Aircraft Division as part of the anti-aircraft defences for the North East. On 1 August 1940, it was transferred to the Royal Artillery as the 53rd (Royal Northumberland Fusiliers) Searchlight Regiment, Royal Artillery and transferred to 57th Anti-Aircraft Brigade. It remained as a searchlight regiment in the UK until January 1945.

In January 1945, the diminishing threat of the Luftwaffe coupled with a manpower shortage in 21st Army Group, particularly in the infantry, led to the conversion of surplus anti-aircraft and coastal artillery regiments in the UK into infantry units. 53rd Searchlight Regiment was one of the regiments selected but it did not revert to its original title, instead becoming 638th (Royal Northumberland Fusiliers) Regiment, Royal Artillery on 23 January 1945. It joined 304th Infantry Brigade, initially in the UK but in Norway from June 1945. It was placed in suspended animation in Norway on 13 December 1945.

7th Battalion At the outbreak of the war, the 7th Battalion was organized as a machine gun battalion in Northumbrian Area, Northern Command. The battalion joined the British Expeditionary Force (BEF) in France in October 1939. It was assigned to III Corps and attached to the 51st (Highland) Infantry Division, which had been stationed at the Maginot Line, and escaped being encircled with the rest of the BEF during the Battle of Dunkirk. It was then pulled back to the west of Northern France, where it was attached to the French Tenth Army. For some time, the 51st was forced to hold a line four times longer than that which would normally be expected of a division. During this period, the 154th Infantry Brigade was detached and withdrawn successfully. However, the 152nd and 153rd Infantry Brigades were trapped at Saint-Valery-en-Caux, and surrendered on 12 June.