The 1st Tank Battalion was formed from these former armoured units on 2 December 1939 and left the camp at Coëtquidan for the village of Campenéac.

The soldiers' morale was low because of the harsh winter conditions, lack of equipment, and poor living quarters.

On 27 May 1940, under the command of Major Stanisław Gliński, it moved to Versailles, where it received modern tanks and equipment.

On 8 June 1940, the Battalion was deployed to Champagne, where the 10th Motorized Cavalry Brigade, under the command of General Maczek, was located.

The Battalion, from the day it arrived in Champagne on 12 June 1940, sustained heavy losses, due to German air attacks.

During its 4 months there, the Battalion was reorganized and brought to full strength by the return of 1st Company, but it still lacked equipment.

In the summer of 1941, the Battalion's duties included: protecting nearby airfields; guarding Broughty Ferry on the Scottish East Coast; and building anti-invasion obstacles around Dundee.

In addition to their military duties, the Battalion assisted the local population with the harvesting of wheat and potatoes.

In both Blairgowrie and Duns, the Battalion left commemorative plaques, thanking the local population for their hospitality.

From May till the end of September 1943, the Regiment participated in Divisional manoeuvers in south-east England near Bury St. Edmunds in Suffolk.

At this time, the Regiment had begun to receive its final allocation of equipment, which included Sherman and Stuart tanks.

As part of the 1st Polish Armoured Division, it was ordered to attack the heavily defended German lines at Falaise.

The 1st Armoured Regiment had broken the German defences by the Laison River and reached Hill 111.

During the action on Hill 111, the 1st Armoured Regiment freed from the Germans about 100 Canadian soldiers who had been without food and ammunition for 2 days.

On 19 August 1944 by 1539hrs, the 1st Armoured Regiment reported that with all their forces, they had taken the area of Coudehard and they were heavily engaged with Panther tanks and heavy enemy artillery fire.

The 1st Polish Armoured Division had borne the whole burden of battle this day against a superior enemy force consisting of units of the 1st and 2nd SS Corps.

[11] On 21 August 1944, a platoon of the Regiment's 3rd Squadron reconnoitred the German positions below the Zameczek ( a hunting lodge on the ridge of Hill 262's northern slope).

[10] The final German effort was launched at around 1100hrs by SS remnants that had infiltrated through the wooded hills to the rear of the 1st Armoured Regiment's dressing station.

This "suicidal" assault was defeated at point-blank range by the 9th Infantry Battalion, with the 1st Armoured Regiment's tanks using their anti-aircraft machine guns in support.

The machine gun's tracer set fire to the grass amongst the German troops, killing the wounded men on the slope.

Their task was: to defend the area to the East and the North; to link up and maintain contact with the 4th Canadian Armoured Division in St Lambert Sur Dives and to link up and maintain contact with the American troops South of Frenes.

In the evening, General Crear of the Canadian Army Command commended the 1st Armoured Division for their actions.

[10] The period between 19 and 21 August 1944 saw a life and death struggle for the Germans trapped in the Falaise Pocket and for the Regiment.

[10] On this day, 1st Armoured Regiment bypassed Ypres, thus cutting off the retreat of the Germans, who were still occupying the town.

After bypassing Thielt (the town Tielt), the Regiment engaged the enemy in the Ruysselede (Ruiselede) area on September 8, 1944.

On 19 September 1944, patrols of the 1st Armoured Regiment detached in the direction of Axelsche – Sabuek encountered enemy forces along the Spun – Kreek Canal.

On 4 October 1944 at 1415hrs, 9th Rifle Brigade plus one Anti-Tank Battery and one squadron from the 1st Armoured Regiment captured the western outskirts of the forest near Baarle-Nassau.

In January–February 1945, the Regiment took up positions on the peninsula of St Philipsland and the island of Tholen, where there was heavy enemy activity.

For the following 2 days, the Regiment battled the enemy north of Papenburg and seized the communication center of Ihrhove-Ihren.

They had experienced the Russian occupation of eastern Poland, when Russia was allied with Germany at the start of the war.