OCR Specification focus:
‘the outbreak and expansion of war in Europe’
The outbreak and expansion of the Second World War in Europe stemmed from political tensions, aggressive foreign policies, and diplomatic failures, rapidly escalating into continent-wide conflict.
The Outbreak of War in Europe
Hitler’s Expansionist Aims
Adolf Hitler’s foreign policy was driven by the pursuit of Lebensraum (living space) in Eastern Europe, the reversal of the Treaty of Versailles, and the unification of all German-speaking peoples. These aims directly challenged the post-First World War order and made conflict increasingly likely.
Lebensraum: The concept in Nazi ideology of securing living space in Eastern Europe to ensure the growth and survival of the German people.
Following Germany’s remilitarisation of the Rhineland (1936), the Anschluss with Austria (1938), and the occupation of Czechoslovakia (1939), it was clear that appeasement would not restrain Hitler’s ambitions.
The Invasion of Poland
The immediate trigger for the Second World War was Germany’s invasion of Poland on 1 September 1939. Hitler demanded the return of Danzig and control over the Polish Corridor, but negotiations failed.
Germany signed the Nazi–Soviet Pact (August 1939), a non-aggression treaty with the USSR, which included a secret protocol dividing Eastern Europe into spheres of influence.
This pact removed the risk of a two-front war for Germany and made the invasion of Poland strategically feasible.
Britain and France had guaranteed Polish independence and, following the invasion, declared war on Germany on 3 September 1939.
The Phoney War
From September 1939 to April 1940, the war on the Western Front was marked by inactivity, known as the Phoney War.
Britain and France mobilised their armies but avoided direct engagement.
Germany consolidated its position in Poland and prepared for wider offensives.
Naval engagements, such as the sinking of the Graf Spee at the River Plate, provided early conflict outside continental Europe.
The Expansion of War in Europe
The Fall of Scandinavia
In April 1940, Germany launched invasions of Denmark and Norway to secure vital resources, particularly Swedish iron ore shipped via Narvik.
Denmark fell within hours, while Norway resisted longer with British and French support.
By June 1940, both countries were under German control, ensuring access to resources and strengthening naval positioning.
Blitzkrieg in the West
The German offensive in the West began in May 1940 with the rapid Blitzkrieg strategy (lightning war), combining fast-moving armour, motorised infantry, and air support.
Simplified campaign diagram of Fall Gelb showing the main German armoured thrust through the Ardennes, the Meuse crossings, and the sweep to the Channel. Routes are clearly traced and key rivers and cities are labelled, making the operational concept easy to grasp. As an SVG, it scales cleanly for classroom display. Source
Germany bypassed the Maginot Line by invading through Belgium and the Ardennes.
The Netherlands and Belgium were quickly overrun.
The British Expeditionary Force and French troops were encircled, leading to the evacuation at Dunkirk (May–June 1940), which saved over 300,000 Allied soldiers.
DEFINITION
Blitzkrieg: A German military tactic meaning “lightning war”, characterised by rapid, concentrated attacks using tanks, aircraft, and motorised infantry to overwhelm the enemy.
The Fall of France
Paris fell on 14 June 1940, and an armistice was signed on 22 June 1940, dividing France into the German-occupied north and the collaborationist Vichy regime in the south.
Britain now stood alone against Germany.
The Battle of Britain
Hitler’s Operation Sea Lion (the planned invasion of Britain) required air superiority.
The Luftwaffe launched air attacks on RAF bases and later cities in the Blitz (1940–1941).
The RAF’s resistance, aided by radar technology and effective fighter command, ensured Germany’s failure to dominate the skies.
This marked Hitler’s first major defeat and forced a shift towards targeting the USSR.
The Expansion to the Balkans
By 1941, Germany expanded further into South-Eastern Europe:
Italy’s failed invasion of Greece in 1940 forced German intervention.
Yugoslavia and Greece were invaded in April 1941, consolidating Axis control of the Balkans.
Operation Barbarossa and the Eastern Front
The ultimate expansion of war came with Operation Barbarossa (22 June 1941), the largest invasion in history, as Germany attacked the Soviet Union.
Three million German troops advanced along three fronts: towards Leningrad, Moscow, and Kiev.
Initial gains were vast, but the campaign stalled by winter due to Soviet resistance, logistical overstretch, and harsh weather.
This opened a brutal Eastern Front and transformed the war into a global conflict.
Key Factors Behind the Expansion
The rapid expansion of war in Europe can be attributed to several factors:
Aggressive German strategy: Blitzkrieg tactics allowed swift conquest.
Weak Allied response: Britain and France were initially slow to act, relying on appeasement and then defensive strategies.
Axis opportunism: Italy and Germany exploited instability in the Balkans and Scandinavia.
Strategic alliances: The Nazi–Soviet Pact enabled expansion without Soviet interference until 1941.
Technological advances: Tanks, aircraft, and mechanised forces created mobility and shock power unmatched by traditional defensive strategies.
FAQ
The Nazi–Soviet Pact ensured Germany could invade Poland without fear of Soviet intervention, effectively neutralising the eastern front.
Secret clauses divided Eastern Europe into German and Soviet spheres of influence, making the invasion strategically viable.
For Britain and France, the pact confirmed Hitler’s intentions and left them little choice but to declare war after Poland’s invasion.
The evacuation of over 300,000 British and Allied troops from Dunkirk preserved a core fighting force that could defend Britain.
While much equipment was abandoned, the successful rescue bolstered morale.
It also marked a failure of German strategy to annihilate the Allies entirely, leaving Britain in the war rather than negotiating peace.
The battle demonstrated that air power could decisively shape strategic outcomes.
Britain’s victory preserved it as a base for future Allied offensives.
It secured Atlantic supply lines by preventing German naval dominance.
It was also the first major defeat for Hitler, undermining the myth of German invincibility.
Germany’s supply lines stretched over vast distances, far beyond what their transport infrastructure could sustain.
Poor roads and the Russian climate slowed advances.
Inadequate fuel and ammunition resupply limited Blitzkrieg’s effectiveness.
Harsh winter conditions immobilised vehicles and weakened troops.
These factors allowed Soviet forces time to regroup and counter-attack.
Mussolini’s unsuccessful campaigns in Greece and Albania forced Hitler to divert resources to the Balkans in 1941.
This delayed Operation Barbarossa by several weeks, meaning the German invasion of the Soviet Union began later in the year than planned.
The diversion contributed to Germany’s inability to reach Moscow before the onset of the severe Russian winter.
Practice Questions
Question 1 (2 marks):
In which year did Germany launch Operation Barbarossa against the Soviet Union?
Mark Scheme:
1 mark for the correct year.
Correct answer: 1941.
(Total: 2 marks)
Question 2 (6 marks):
Explain two reasons why Germany was able to defeat France so quickly in 1940.
Mark Scheme:
Up to 3 marks per reason explained.
Award 1 mark for simple identification of a reason, 2 marks for identification with some explanation, 3 marks for a developed explanation showing clear understanding.
Indicative content may include:
Blitzkrieg tactics: the use of fast-moving tanks, aircraft, and motorised infantry to overwhelm French defences.
Invasion through the Ardennes: bypassing the Maginot Line and catching Allied forces unprepared.
Allied weaknesses: reliance on static defence and slow response to German mobility.
German air superiority: Luftwaffe support disrupted Allied communications and movements.
(Total: 6 marks)
