Normandy Commanded by
General Sir Bernard Montgomery, 21st Army Group initially controlled all ground forces in
Operation Overlord (the
United States First Army and
British Second Army). When sufficient American forces had landed, their own
12th Army Group was activated, under
General Omar Bradley, and the 21st Army Group was left with the British Second Army and the newly activated
First Canadian Army which, despite its title, also contained many British and Polish troops. Normandy was a battle of attrition for the British and Canadian troops, drawing in most of the available German reinforcements, especially armoured divisions, around
Caen at the eastern end of the
lodgement. These operations left the Germans unable to prevent the
American breakout at the western end of the Normandy beachhead in early August 1944. Following the
German attack towards Mortain, the American breakout and an advance by the 21st Army Group the German armed forces in Normandy were nearly enveloped in the
Falaise pocket, and subsequently routed, retreating towards the Low Countries.
Advance into the Low Countries After the successful
landings in the south of France by the
US 6th Army Group, the 21st Army Group formed the left flank of the three Allied army groups arrayed against German forces in the West. It was therefore responsible for securing the ports upon which Allied supply depended, and also with overrunning German
V-1 and
V-2 launching sites along the coasts of western
France and
Belgium. By 29 August, the Germans had largely withdrawn across the
Seine River without their heavy equipment. The campaign through Northern France and Belgium was largely a pursuit, with the ports – formally designated "Fortress Towns" by the Germans – offering only limited opposition to the First Canadian Army. The advance was so rapid, 250 miles in four days, that
Antwerp, Belgium, was captured undefended on 4 September 1944 and the port facilities were cleared of the German defenders in the following days. On 1 September 1944, the 21st Army Group was relieved of operational control of the American armies, and those armies formed the
12th Army Group. At the same time, Montgomery was promoted to Field Marshal. By mid-September, elements of 21st Army Group had reached the Dutch border, but were halted due to lack of supplies, and by flooding caused by the widespread German demolition of Dutch dikes. German control of some of the channel ports and the approaches to Antwerp, and previous Allied bombing of the French and Belgian railways, resulted in a long supply line from Normandy served mainly by
trucks.
Operation Market Garden After the break-out from Normandy, there were high hopes that the war could be ended in 1944. In order to do so, the last great natural defensive barrier of Germany in the west, the
Rhine River had to be crossed.
Operation Market Garden was orchestrated to attempt just this. It was staged in the
Netherlands with the
airborne troops of the American
82nd and
101st and one British
1st airborne divisions and the
1st Polish Parachute Brigade (attached to the 1st Airborne Division) being dropped to capture bridges over the lower Rhine before they could be blown by the Germans. The airborne formations were then to be relieved by armoured forces of the
Guards Armoured Division advancing rapidly northwards through
Eindhoven and
Nijmegen to
Arnhem, opening the north German plains, and the industrial
Ruhr Valley, to the Allies. The advance stopped south of the
Lower Rhine, resulting in a narrow salient that ran from the north of Belgium across the south-east of the Netherlands and was vulnerable to attack. German assaults in this salient, particularly north of Nijmegen
were repelled. The thin salient was then expanded Eastwards with
Operation Aintree which saw bitter fighting around the town of
Overloon. To the West
Operation Pheasant was conducted which resulted in the liberation of the cities of
Tilburg and
's-Hertogenbosch broadening the front line.
Battle of the Scheldt Since the approaches to the port of
Antwerp had not been cleared when the city was captured it had allowed the German army time to reorganise and dig in along the approaches making the port completely unusable. Thus an operation was needed to clear the approaches and thereby ease the supply problem. The island of
Walcheren was strongly held by German forces and commanded the estuary of the
Scheldt which flows through Antwerp. Operations by
II Canadian Corps cleared the approaches to Antwerp both north and south of the water during the
Battle of the Scheldt. Walcheren itself was captured in late 1944 by the last major amphibious assault in Europe in the Second World War. A combination of British and Canadian forces and
Royal Marines undertook the operation.
Battle of the Bulge After the capture of Walcheren came the last great German offensive of the war in the west. In a repeat of their 1940 attack, German formations smashed through weak Allied lines in the
Ardennes in Belgium. The
Battle of the Bulge presented a command problem to General
Eisenhower. It had sliced through US lines, leaving some American formations north and south of the new German salient. However, the headquarters of the US 12th Army Group lay to the south, and so Eisenhower decided to place American forces north of the "Bulge" salient under 21st Army Group. They, with the
US Third Army under General
George S. Patton, reduced the salient. After the battle, control of the First US Army which had been placed under Field Marshal Montgomery's temporary command was returned to Bradley's 12th Army Group. The
US Ninth Army remained under Montgomery longer, before being returned to American command in Germany.
Battle for the Roer Triangle Prior to the Rhineland Campaign the enemy had to be cleared from the
Roer Triangle during
Operation Blackcock. This large methodical mopping up operation took place between 14 and 27 January 1945. It was not planned to make any deep thrust into the enemy defences or capture large numbers of prisoners. It proceeded from stage to stage almost entirely as planned and was completed with minimal casualties.
Rhineland Campaign Allied forces closed up to the Rhine by March 1945. 21st Army Group at this time comprised the British Second Army under General
Miles Dempsey, the First Canadian Army under
General Harry Crerar and the US Ninth Army, under General
William Simpson. The First Canadian Army executed
Operation Veritable in difficult conditions from
Nijmegen eastwards through the Reichswald Forest then southwards. This was to have been the northern part of a pincer movement with the US Ninth Army moving northwards towards
Düsseldorf and
Krefeld (
Operation Grenade), to clear the west bank of the Rhine north of
Cologne. However the Americans were delayed by two weeks when the Germans destroyed the
Roer dams and flooded the American route of advance. As a result, the Canadians engaged and mauled the German reserves intended to defend the Cologne Plain. In
Operation Plunder, starting on 13 March 1945, the British Second Army and the US Ninth Army crossed the Rhine at various places north of the Ruhr and German resistance in the west quickly crumbled. The First Canadian Army wheeled left and liberated the northern part of the Netherlands and captured adjoining areas of Germany, the British Second Army occupied much of north-west Germany and the US Ninth Army formed the northern arm of the
envelopment of German forces in the
Ruhr Pocket and on 4 April reverted to Omar Bradley's 12th Army Group. ==British Army of the Rhine==