World War II emerged from a complex web of factors in the aftermath of World War I. The rise of fascism, economic turmoil, and aggressive nationalism set the stage for conflict. Failed diplomacy and appeasement emboldened expansionist powers like Germany and Italy.

The immediate trigger came with Germany's invasion of Poland in 1939. This act of aggression prompted Britain and France to declare war, marking the official start of World War II. The conflict would reshape global power structures and leave lasting impacts.

Rise of fascism

• Fascism emerged as a political ideology in the aftermath of World War I, gaining popularity in several European countries, particularly Italy and Germany
• Fascist movements were characterized by extreme nationalism, authoritarianism, and often racism, seeking to establish a strong, centralized state led by a dictatorial leader

Fascist ideology

• Emphasized the superiority of the nation and the importance of national unity, often at the expense of individual rights and freedoms
• Promoted a corporatist economic system, in which the state, employers, and workers collaborate for the benefit of the nation
• Advocated for aggressive foreign policies, including expansionism and militarism
• Scapegoated minority groups, such as Jews, for societal problems and economic hardships

Mussolini in Italy

• Benito Mussolini founded the Italian Fascist Party in 1919 and became the Prime Minister of Italy in 1922
• Established a totalitarian regime, known as the "Italian Social Republic," which suppressed political opposition and individual freedoms
• Implemented economic policies aimed at modernizing Italy and increasing its military strength
• Formed an alliance with Nazi Germany in the late 1930s (Pact of Steel)

Hitler and the Nazi Party

• Adolf Hitler joined the National Socialist German Workers' Party (Nazi Party) in 1919 and became its leader in 1921
• Exploited the economic and political instability of the Weimar Republic to gain popular support
• Appointed as Chancellor of Germany in 1933 and quickly consolidated power, establishing a totalitarian dictatorship
• Implemented racist policies, particularly targeting Jews, and pursued an aggressive foreign policy that ultimately led to World War II

Aftermath of World War I

• World War I (1914-1918) had a profound impact on Europe, leading to significant political, economic, and social changes that contributed to the rise of fascism and the eventual outbreak of World War II
• The war resulted in the collapse of empires, the redrawing of national boundaries, and the emergence of new states, creating a fragile and unstable political landscape

Treaty of Versailles

• The Treaty of Versailles (1919) officially ended World War I and imposed harsh terms on Germany, including significant territorial losses, military restrictions, and substantial war reparations
• Many Germans viewed the treaty as unfair and humiliating, fueling resentment and nationalism that would later be exploited by Hitler and the Nazi Party
• The treaty also created new nations and borders in Europe, often without considering ethnic and cultural divisions, leading to further instability

Economic devastation

• World War I had a severe economic impact on Europe, with many countries experiencing high levels of debt, inflation, and unemployment
• The Great Depression, which began in 1929, exacerbated these economic problems, leading to widespread poverty and social unrest
• Economic hardship and uncertainty made fascist movements, which promised stability and national revival, more appealing to many Europeans

Resentment and nationalism

• The aftermath of World War I and the perceived injustices of the Treaty of Versailles fueled a sense of resentment and nationalism in many European countries, particularly Germany
• Nationalist movements, such as the Nazi Party in Germany, gained popularity by promising to restore national pride and rectify the perceived wrongs of the post-war settlements
• The rise of nationalism also contributed to increasing tensions between European states, as countries sought to assert their interests and expand their influence

Appeasement and diplomacy

• In the years leading up to World War II, European leaders pursued policies of appeasement and diplomacy in an attempt to maintain peace and prevent another devastating conflict
• However, these efforts ultimately failed to curb the aggressive ambitions of fascist states like Germany and Italy, and may have even emboldened them

Failure of the League of Nations

• The League of Nations, established after World War I to promote international cooperation and prevent future wars, proved ineffective in dealing with aggressive states
• The League lacked a strong enforcement mechanism and was often undermined by the absence of major powers, such as the United States, and the reluctance of member states to take decisive action
• The League's failure to prevent the Italian invasion of Ethiopia (1935) and the Japanese invasion of Manchuria (1931) demonstrated its weakness and diminished its credibility

British and French policies

• Britain and France, the two major European powers, initially pursued policies of appeasement towards Germany and Italy, hoping to avoid another war
• British Prime Minister Neville Chamberlain and French leaders believed that by making concessions to Hitler and Mussolini, they could satisfy their demands and maintain peace
• These policies, however, only served to encourage further aggression, as fascist leaders interpreted appeasement as a sign of weakness and an opportunity to expand their power

Munich Agreement

• The Munich Agreement (1938) was a prime example of appeasement, in which Britain, France, Italy, and Germany agreed to the German annexation of the Sudetenland, a region of Czechoslovakia with a significant ethnic German population
• The agreement was hailed by Chamberlain as guaranteeing "peace for our time," but in reality, it only emboldened Hitler and paved the way for further German expansionism
• The Munich Agreement also undermined the security of Czechoslovakia and other Eastern European states, leaving them vulnerable to Nazi aggression

Expansionism and aggression

• Fascist states, particularly Germany, Italy, and Japan, pursued aggressive foreign policies aimed at expanding their territories and influence in the years leading up to World War II
• These policies were driven by a combination of ideological beliefs, economic interests, and a desire to revise the post-World War I international order

German rearmament

• In violation of the Treaty of Versailles, Germany began rearming in the 1930s under Hitler's leadership
• Hitler withdrew Germany from the League of Nations in 1933 and introduced conscription in 1935, rapidly expanding the German military
• The remilitarization of the Rhineland (1936) and the Anschluss (annexation) of Austria (1938) were early examples of German expansionism that went unchallenged by other European powers

Italian invasion of Ethiopia

• In 1935, Fascist Italy, led by Mussolini, invaded Ethiopia, one of the few remaining independent African states
• The League of Nations condemned the invasion but failed to take effective action, revealing its weakness and emboldening Mussolini
• The Italian conquest of Ethiopia (1936) demonstrated the growing aggression of fascist states and the ineffectiveness of international institutions in preventing conflict

Japanese invasion of Manchuria

• In 1931, Japan invaded and occupied Manchuria, a region of northeastern China, establishing the puppet state of Manchukuo
• The League of Nations condemned the invasion but did not take strong action against Japan, which withdrew from the League in 1933
• The Japanese invasion of Manchuria marked the beginning of Japanese expansionism in Asia and contributed to rising tensions in the region

Alliances and tensions

• In the years leading up to World War II, Europe became increasingly polarized as countries formed alliances and tensions between states escalated
• The formation of opposing alliances, combined with the aggressive foreign policies of fascist states, made the outbreak of a major conflict increasingly likely

Axis powers

• The Axis powers were an alliance of fascist and militaristic states that emerged in the 1930s, primarily consisting of Germany, Italy, and Japan
• Germany and Italy formalized their alliance with the Pact of Steel (1939), while Japan and Germany signed the Anti-Comintern Pact (1936) to oppose the spread of communism
• The Axis powers shared a common goal of expanding their territories and influence, often through military aggression and conquest

Allied powers

• The Allied powers, also known as the Allies, were a coalition of nations that opposed the Axis powers during World War II
• Initially, the Allies consisted primarily of Britain and France, but the alliance expanded to include the United States, the Soviet Union, and other countries as the war progressed
• The Allies sought to contain the expansion of fascist states and ultimately defeat the Axis powers to restore peace and stability to Europe and the world

Polarization of Europe

• The rise of fascism, the formation of opposing alliances, and the pursuit of aggressive foreign policies by states like Germany and Italy led to a growing polarization of Europe in the 1930s
• Countries increasingly viewed international relations as a zero-sum game, with the gains of one state coming at the expense of others
• This polarization, combined with the failure of appeasement and the weakness of international institutions, made the outbreak of a major conflict more likely

Immediate triggers

• While the underlying causes of World War II were complex and long-standing, a series of immediate events in 1939 directly triggered the outbreak of the conflict
• These events, particularly the German invasion of Poland and the subsequent declarations of war by Britain and France, marked the beginning of the war in Europe

German invasion of Poland

• On September 1, 1939, Germany invaded Poland, using a staged attack on a German radio station as a pretext for the invasion
• The German invasion, carried out in coordination with the Soviet Union as per the Molotov-Ribbentrop Pact (1939), quickly overwhelmed Polish defenses
• The invasion of Poland demonstrated Hitler's willingness to use military force to achieve his expansionist goals and marked the beginning of World War II in Europe

Declarations of war

• In response to the German invasion of Poland, Britain and France, honoring their commitments to Poland, declared war on Germany on September 3, 1939
• The declarations of war by Britain and France marked the official beginning of World War II, as the conflict expanded beyond a localized dispute
• Other countries, such as Canada, Australia, and New Zealand, soon followed suit, declaring war on Germany in support of Britain and France