Second World War
In 1939 a British Expeditionary Force was again sent to France to support the French Army. This force included The 2nd Royal Inniskilling Fusiliers, 2nd Royal Ulster Rifles and 1st Royal Irish Fusiliers. All three battalions played their part in the retreat to Dunkirk. The Inniskillings formed part of the rearguard and only 215 were eventually evacuated. The Royal Irish Fusiliers alone held a German Panzer division for almost three days.
In early 1942 the 38th (Irish) Brigade was formed: it included The 6th Inniskillings, 1st Irish Fusiliers and 2nd London Irish. As part of First Army the Irish Brigade served in Tunisia and took part in the breakthrough to Tunis in the spring of 1943. It then fought, with Eighth Army, in the brief Sicilian campaign where 6th Inniskillings captured the mountain top town of Centuripe.
The Brigade then moved to Italy and played a vital role in the Allied breaking of the Gustav Line at Cassino in May 1944. It was the cutting of Highway 6 by the Irish Brigade that forced the Germans to abandon the Monte Cassino strong point. Following that success the Brigade went on to Lake Trasimene and distinction in the battles that broke the Albert Line. In early 1945 the Irish Brigade's final actions in Italy included the smashing of the Argenta Gap where the London Irish Rifles fought as mechanised infantry in the Kangaroo Army, an all-arms battle group. 1st London Irish Rifles fought in Sicily and Italy as well and their battle honours include Anzio where 2nd Inniskillings also fought. After the breakout from Anzio and the final Cassino battle, 2nd Inniskillings joined The Irish Brigade to replace 6th Inniskillings who were disbanded.
In North-West Europe The Royal Ulster Rifles had the unique distinction of being the only regiment in the British Army to have its two regular battalions included in the invasion of Normandy - Operation Overlord - on 6 June 1944. One battalion landed from the sea while the other was airborne. Both battalions fought through the subsequent campaign until the end of the war in Europe.
In the Far East 1st Royal Inniskilling Fusiliers had been sent from India to Burma when the Japanese invaded that country. The battalion suffered heavily as British forces retreated and just over a hundred men returned to India. In the Arakan campaign of 1943 the battalion again had heavy losses in action against the Japanese at Donbaik.
The Royal Irish Fusiliers lost their Second Battalion when the island of Leros fell to the Germans in late 1943. The Battalion had earlier taken part in the defence of Malta during the siege of that island; 6th Royal Irish Fusiliers reformed as 2nd Royal Irish Fusiliers after the original battalion was captured on Leros.