The course of the European war 1939 to 1941, including the invasion of Poland, the Phoney War, the German conquest of Western Europe in 1940, the Battle of Britain, and Operation Barbarossa of June 1941

What this dot point is asking

NESA expects you to describe and analyse the early course of the European war from September 1939 to December 1941, when Germany was strategically on the offensive and the war's outcome had not yet turned. Strong answers cover Poland, the Phoney War, Norway, the fall of France, the Battle of Britain, the Mediterranean and Balkans campaigns, and Operation Barbarossa. The historiographical frame is Overy (the operational mastery and its strategic limits), Beevor (operational detail), and Glantz (Soviet perspective on Barbarossa).

The answer

The invasion of Poland, September 1939

Five German armies invaded Poland on 1 September 1939: Army Group North under Bock, Army Group South under Rundstedt, attacking from East Prussia, Slovakia, and Silesia. The Wehrmacht deployed around 1.5 million men, 2,500 tanks, and 2,000 aircraft.

The Luftwaffe under Kesselring destroyed most of the Polish Air Force on the ground in the first 48 hours. Polish armies fought hard at the Bzura (9 to 19 September) but were enveloped. The USSR invaded eastern Poland on 17 September under the secret Pact protocols. Warsaw surrendered on 27 September; the last Polish regular forces surrendered on 6 October.

Polish casualties: around 70,000 killed, 130,000 wounded, 690,000 prisoners. The campaign was the first demonstration of Blitzkrieg: combined-arms mechanised warfare with close air support and operational depth.

The Phoney War, September 1939 to April 1940

The Western Front remained largely quiet through the winter. Britain dispatched the British Expeditionary Force (BEF) to France under Lord Gort; both Allied armies took up defensive positions along the Belgian frontier and behind the Maginot Line. The Saar offensive (September 1939) was a token French advance that withdrew within days.

The USSR invaded Finland on 30 November 1939 (the Winter War). Finnish resistance under Mannerheim inflicted heavy Soviet casualties before the Moscow Peace Treaty of 13 March 1940. The Red Army's poor showing reinforced German contempt for Soviet military capability and contributed to Hitler's overconfidence about Barbarossa.

Norway and Denmark, April 1940

Operation Weserubung began on 9 April 1940 with simultaneous German invasions of Denmark and Norway, partly to secure iron-ore supplies from neutral Sweden through Narvik. Denmark surrendered the same day. Norway fought on with Allied support; British and French forces landed at Narvik but were withdrawn after the German offensive in the west.

The Royal Navy fought two naval battles at Narvik (10 and 13 April 1940), sinking most of the German destroyer force. Norwegian resistance under King Haakon continued from London; Vidkun Quisling's collaborationist regime in Oslo coined the eponym.

The Norway campaign brought down the Chamberlain government. The Norway Debate (7 to 8 May 1940) saw Conservative rebels vote with Labour. Churchill became Prime Minister on 10 May 1940, the day Germany attacked the West.

The Fall of France, May to June 1940

Operation Fall Gelb began on 10 May 1940. The plan, refined by Manstein and Halder (the Sichelschnitt or "sickle cut"), concentrated German armour in Army Group A under Rundstedt for a thrust through the Ardennes, considered impassable by the French High Command.

Heinz Guderian's panzers crossed the Meuse at Sedan on 13 to 14 May. The French Ninth Army (Corap) broke. Guderian raced for the Channel, reaching Abbeville on 20 May. The trapped Allied forces (BEF, French First Army, Belgian army) were squeezed against the coast.

The Dunkirk evacuation (Operation Dynamo, 26 May to 4 June 1940) rescued around 338,000 Allied troops by a flotilla of warships, merchant ships, and small craft, helped by Hitler's controversial 24 May halt order. The BEF lost most of its equipment but preserved its men.

Italy declared war on France and Britain on 10 June 1940. Paris fell on 14 June. Marshal Petain replaced Reynaud and signed the armistice at Compiegne on 22 June 1940, in the same railway carriage where Germany had signed in 1918. France was divided into an occupied zone (north and west) and an unoccupied zone under Petain's Vichy government.

Charles de Gaulle, French Under-Secretary for War, flew to London and broadcast the appeal of 18 June calling on French forces to continue the fight.

The Battle of Britain, July to October 1940

Hitler's Directive 16 (16 July 1940) ordered planning for Operation Sealion, the invasion of Britain. The precondition was air superiority over southern England.

The battle moved through phases:

• Kanalkampf (July to early August): attacks on Channel convoys and ports.
• Adlertag (Eagle Day, 13 August) and Adlerangriff: attacks on RAF airfields and radar stations.
• The shift to London (from 7 September), partly retaliation for a small RAF raid on Berlin, partly mistaken intelligence.
• The climax around 15 September (Battle of Britain Day), with heavy Luftwaffe losses.

RAF Fighter Command was commanded by Air Chief Marshal Hugh Dowding; 11 Group (southern England) by Air Vice-Marshal Keith Park. The Chain Home radar network gave early warning. Hurricanes and Spitfires equipped the squadrons. Lord Beaverbrook's Ministry of Aircraft Production sustained replacement rates.

Losses to 31 October: Luftwaffe around 1,887 aircraft and over 2,500 aircrew; RAF around 1,023 aircraft and 537 aircrew killed. Operation Sealion was postponed indefinitely on 17 September 1940.

The night bombing of London and other cities (the Blitz) continued through 1940 to 1941. Coventry was severely bombed on 14 November 1940. Around 43,000 British civilians were killed by 1941.

The Mediterranean and the Balkans, 1940 to 1941

Italy's invasion of Greece (28 October 1940) failed; the Greeks counter-attacked into Albania. The Italian Tenth Army's attack into Egypt (September 1940) was destroyed by General Wavell's Operation Compass (December 1940 to February 1941), which captured around 130,000 Italian prisoners.

German intervention followed. Erwin Rommel was sent to North Africa with the Deutsches Afrika Korps from February 1941 and rapidly drove the British back to the Egyptian frontier. The Balkans campaign began with the German invasion of Yugoslavia and Greece (6 April 1941); both fell within weeks. The German airborne assault on Crete (Operation Mercury, 20 May to 1 June 1941) succeeded at heavy cost to the Fallschirmjager.

The Mediterranean campaigns consumed German resources and delayed Barbarossa by around five weeks, a delay Hitler would later blame for the failure at Moscow.

Operation Barbarossa, June to December 1941

Operation Barbarossa, the German invasion of the USSR, began at 3.15 am on 22 June 1941. Three German Army Groups attacked:

• Army Group North under Leeb advanced from East Prussia towards Leningrad.
• Army Group Centre under Bock attacked through Belorussia towards Moscow.
• Army Group South under Rundstedt attacked through Ukraine.

Total Axis forces: around 3.8 million men, 3,600 tanks, 2,700 aircraft. The Red Army was caught in a forward deployment despite intelligence warnings (the Sorge reports from Tokyo, the British and American warnings).

Initial successes were vast. Encirclements at Bialystok-Minsk (June to July) and Smolensk (August) trapped over a million Soviet soldiers. The Kiev encirclement (mid-September) trapped a further 660,000. By November, Army Group Centre had advanced to within 30 km of Moscow.

The Wehrmacht had no clothing or equipment for the Russian winter; the autumn rasputitsa (mud season) and then severe cold halted operations. The Soviets, with fresh Siberian divisions transferred after Sorge's intelligence ruled out a Japanese attack, launched a counter-offensive at Moscow on 5 December 1941. Operation Typhoon, the Moscow drive, had failed.

On 7 December 1941 Japan attacked Pearl Harbor. On 11 December Hitler declared war on the United States. The European war was now a world war.

Timeline of 1939 to 1941

Historiography

Richard Overy (Why the Allies Won, 1995) treats German operational excellence as resting on an inadequate strategic and economic foundation; the wins of 1939 to 1941 created the conditions for the defeat that followed.

Antony Beevor (The Second World War, 2012; Stalingrad, 1998) is the modern operational and human standard.

David Glantz (When Titans Clashed, 1995) is the standard work on the Eastern Front from the Soviet side.

Karl-Heinz Frieser (The Blitzkrieg Legend, 2005) argues "Blitzkrieg" was a postwar construction by German generals; the 1940 victory in the West was less doctrinal than improvised. The argument has reshaped operational history.

Adam Tooze (The Wages of Destruction, 2006) integrates the economic constraints on the German war effort.

How to read a source on this topic

Sources on 1939 to 1941 commonly include German propaganda newsreels of the Polish and French campaigns, the Battle of Britain RAF interviews, photographs of Dunkirk, German plans for Operation Barbarossa, Soviet defence orders, and Churchill's speeches. Three reading habits.

First, separate propaganda from operational fact. The 1940 newsreels project Blitzkrieg as flawless German doctrine. Frieser's archival work shows the May 1940 success was improvised; Guderian disobeyed orders to drive on Abbeville. Both the projection and the reality are evidence.

Second, watch for the gap between operational and strategic levels. The Wehrmacht won most operations of 1939 to 1941; the strategic war was decided at Moscow in December 1941 and at Stalingrad in February 1943.

Third, read Barbarossa orders alongside the war crimes context. The Commissar Order (6 June 1941) and the Barbarossa Decree (13 May 1941) authorised summary execution of Soviet political officers and the immunity of German soldiers from prosecution for crimes against Soviet civilians. The military and the ideological wars were the same war.

Common exam traps

Treating Blitzkrieg as a coherent doctrine. Frieser shows it was largely a postwar construction; the 1940 victory was substantially improvised.

Forgetting the Polish campaign. Poland's army fought hard; the defeat was geographical, not technical.

Misdating Operation Sealion's postponement. 17 September 1940, not 31 October.

Treating Barbarossa as a foregone conclusion. The Wehrmacht failed at Moscow in December 1941. The campaign had reached its operational limit.

In one sentence

Between September 1939 and December 1941 Germany conquered Poland in five weeks, won Scandinavia in eight weeks, defeated France in six weeks through the Manstein Ardennes thrust, evacuated the British Expeditionary Force at Dunkirk, failed to gain air superiority over Britain in the Battle of Britain of July to October 1940, intervened in the Mediterranean and Balkans to rescue Italy, and launched Operation Barbarossa on 22 June 1941 with 3.8 million Axis troops on a 2,900 km front before the failure of the Moscow offensive of December 1941 (and Hitler's declaration of war on the United States four days after Pearl Harbor) ended the Blitzkrieg phase and turned the European war into a world war.