Regular Army

The 1st Battalion spent the war on garrison duty in Quetta, Baluchistan, on the North-West Frontier.^[14][15] The 2nd Battalion landed at Le Havre as part of the 7th Brigade in the 3rd Division in August 1914 and spent the entire war on the Western Front.^[14][15]

Special Reserve

The 3rd (Reserve) Battalion spent the whole war in England, initially at Crosby, later at Barrow-in-Furness in the Barrow Garrison, fulfilling its dual role of coast defence and preparing reinforcement drafts of regular reservists, special reservists, recruits and returning wounded for the regular battalions serving overseas. Thousands of men would have passed through its ranks during the war. In September and October 1914, it probably assisted in the formation of 10th (Reserve) Battalion, South Lancashires, at Crosby from Kitchener's Army volunteers.^{[16][17][14][15]}

Territorial Force

The 1/4th Battalion landed at Le Havre as part of the 7th Brigade in the 3rd Division in February 1915 for service on the Western Front.^[14][15] The 1/5th Battalion landed at Le Havre as part of the 12th Brigade in the 4th Division in February 1915 also for service on the Western Front.^[14][15] The 2/4th and 2/5th Battalions landed at Boulogne as part of the 172nd (2/1st South Lancashire) Brigade in the 57th (2nd West Lancashire) Division in February 1917 also for service on the Western Front.^[14][15]

New Army Battalions

The 6th (Service) Battalion landed at Cape Helles in Gallipoli as part of the 38th Brigade in 13th (Western) Division in July 1915;^[14][15] a detachment from the battalion was commanded by Captain Clement Attlee, who fell ill with dysentery during the campaign^[18] but went on to become prime minister.^[19] The battalion was evacuated from Gallipoli and went to Egypt in December 1915 before moving on to Mesopotamia in February 1916.^[14][15]

The 7th (Service) Battalion landed at Boulogne as part of the 56th Brigade in the 19th (Western) Division in July 1915 for service on the Western Front.^[14][15] The 8th (Service) Battalion landed in France as part of the 75th Brigade in the 25th Division in September 1915 also for service on the Western Front.^[14][15] The 9th (Service) Battalion landed in France as part of the 66th Brigade in the 22nd Division in September 1915 for service on the Western Front but transferred to Salonika in November 1915.^[14][15] The 11th (Service) Battalion (St Helens Pioneers) landed at Le Havre as pioneer battalion to the 30th Division in November 1915 for service on the Western Front.^[14][15]

Regular Army

The 1st Battalion, a Regular Army battalion, was shipped to France on the outbreak of war in 1939 as part of the 12th Infantry Brigade, 4th Infantry Division, British Expeditionary Force, returning to England via Dunkirk.^[21] After returning to the United Kingdom, it was transferred to the 8th Infantry Brigade (which included the 1st Suffolk Regiment and 2nd East Yorkshire Regiment) attached to the 3rd Infantry Division, nicknamed Monty's Ironsides. With this division, it landed at Sword Beach on D-Day and fought its way through the Normandy, the Netherlands and later the invasion of Germany.^[21]

The 2nd Battalion was in Bombay in 1939, being transported back to Britain in July 1940 to defend the home front against the expected German invasion. In 1942, commanded by Lieutenant Colonel Michael West, later to become a full general, attached to the 29th Independent Infantry Brigade, it was part of Force 121, which invaded Madagascar in order to prevent use of the island by the Japanese.^[21] From April 1944 until the end of the war, it fought in the recapture of Burma, initially with the 36th Infantry Division alongside the 2nd Battalion, East Lancashire Regiment. The 2nd battalion was then transferred to the 114th Indian Infantry Brigade, 7th Indian Infantry Division, serving with them until July 1945, when the Battalion came under command of the 20th Indian Division.^[22]

Territorial Army

The 2/4th Battalion was raised in 1939 as a 2nd Line Territorial Army battalion duplicate of the 1st Line 4th Battalion, later redesignated the 1/4th Battalion. Both the 1/4th and 2/4th battalions served in the 164th Infantry Brigade, part of the 55th (West Lancashire) Infantry Division. In 1943, the 2/4th Battalion was transferred to the British Army's airborne forces and converted to become the 13th Parachute Battalion of the Parachute Regiment, part of the 5th Parachute Brigade, which itself was part of the newly raised 6th Airborne Division.^[23] The 13th Parachute Battalion saw combat during Operation Tonga, the British airborne landings in the early hours of 6 June 1944, D-Day.^[24] The battalion served as normal infantrymen for the duration of the Battle of Normandy until being withdrawn, with the rest of the division, to England in September 1944. The 6th Airborne Division was then sent to Belgium in December 1944 to fight in the Ardennes offensive, the Battle of the Bulge.^[25] They were then involved in the largest airborne drop of the entire war with over 16,000 airborne troops taking part, known as Operation Varsity, with the US 17th Airborne Division.^[26]

The 5th Territorial Battalion of the regiment was transferred to the Royal Artillery before the war and converted into the 61st (South Lancashire) Searchlight Regiment. It served in North West England, in Orkney, and in Kent against V-1 flying bombs.^[27][28] In late 1944, it became the 61st (South Lancashire Regiment) Garrison Regiment, Royal Artillery. In early 1945, due to a severe shortage of infantrymen in the 21st Army Group, the regiment was converted into the 612th (South Lancashire Regiment) Infantry Regiment, Royal Artillery and joined the 306th Infantry Brigade, thereby releasing trained infantrymen for frontline service.^[27][29]

Hostilities-only

The regiment raised many other battalions for service before and during the war but most were disbanded before the war's end. The 6th (Home Defence) Battalion was raised in 1939 and, in 1941, was redesignated the 30th Battalion. It was disbanded in January 1943.^[30]

The 7th and 8th battalions were both raised in 1940 and joined the 204th Infantry Brigade. On 1 September 1942, the brigade was redesignated the 185th Infantry Brigade and the 7th Battalion was sent to India, where it remained until disbandment in 1946, as a training battalion with the 52nd Brigade. The battalion's role was training British infantry replacements in jungle warfare for the British Fourteenth Army.^[31]

The 50th (Holding) Battalion was raised in 1940. That October, it was redesignated as the 9th Battalion and joined the 225th Infantry Brigade and then the 207th Infantry Brigade. The battalion remained in the United Kingdom for the war and was later transferred to the 164th Infantry Brigade, alongside the 1/4th Battalion, and supplied replacements to units overseas. It was apparently disbanded in July 1944, but another source claims it was disbanded in 1946.^[3]