The battalion took part in Operation Tonga during the D-Day landings, capturing Ranville and held it against several German counter-attacks.

It later fought in the Battle of Breville, and played a part in the 6th Airborne Division advance to the River Seine, after which it was returned to England in September 1944.

[5] By 1944 a headquarters or support company, was added to the battalion comprising five platoons: motor transport, signals, mortar, machine-gun and anti-tank.

[6][8] Airborne soldiers were expected to fight against superior numbers of the enemy, armed with heavy weapons, including artillery and tanks.

Military exercises included capturing and holding airborne bridgeheads, road or rail bridges and coastal fortifications.

[9][nb 2] On 6 June 1944, the 12th Parachute Battalion, under the command of Lieutenant Colonel Johnny Johnson, landed in Normandy at 00:50.

During this time the 12th Parachute Battalion was bombarded with heavy mortar and artillery fire, and repelled two German counter-attacks by the 125th Panzer Grenadier Regiment;[12] the first was defeated after destroying a Tiger tank and taking a number of prisoners, and the second was repulsed with the help of an air-landed anti-tank battery which had recently arrived.

[15] The attack was beaten off for the loss of three tanks, but caused several casualties amongst 'A' Company, including the crew of their only supporting 6 pounder anti-tank gun.

[16] On 9 June two companies of the battalion were ordered to support the Royal Ulster Rifles in their assault on Honorine la Chardonnerette.

[18] The successful capture of the village prevented the German army from using it as a staging area to launch attacks on the River Orne and Caen canal bridgeheads.

[13] After a period of rest and reorganisation the battalion rejoined the 5th Parachute Brigade in preparation for the breakout offensive towards the River Seine.

The three divisions east of the Orne together became I Corps; its commander, Lieutenant-General John Crocker, knowing that the 6th Airborne had almost no artillery, vehicles or engineer equipment, did not expect it to advance very quickly.

[19] The 13th Parachute Battalion attempted to carry out a bayonet assault on Hill 13 however they were forced to withdraw under heavy fire after a German counterattack.

[20] On 21 August, the 3rd Parachute Brigade advanced towards the River Touques at Pont-l'Évêque facing very heavy resistance from German infantry and armour.

The Germans opened fire when they were around 400 yards (370 m) from the river; only ten men from the battalion succeeded in crossing, and then became trapped on the far bank.

Sergeant Dennis Edmund Griss of 'A' Company was awarded the Croix de Guerre for the action.

The next day, patrols from the 7th Parachute Battalion discovered that the Germans had withdrawn during the night, and they therefore crossed the river and secured the high ground to the north, closely followed by the rest of the brigade.

[18] The 12th and 13th battalions then made their way off the drop zone and, after a struggle, established themselves on the Brigade's main objective, covering the road to Hamminkeln.

Simultaneously 12th Battalion marched 20 miles (32 km) across country, and were ready to assault Erle once daylight came.

[13][18][26] On 6 April advancing in the direction of the River Leine, the 12th Parachute Battalion maintained an advance for 30 hours, including 30 miles in 10 hours, and as a result of four major skirmishes, had killed or captured three hundred enemy troops and a considerable amount of war materiel.

In December 1945 the 23rd Indian Division and 5th Parachute Brigade successfully occupied civil administration buildings in Batavia, including all police stations.