How did World War II begin?

Fears mounting that Ukraine invasion could trigger third global war

Adolf Hitler
(Image credit: AFP/Getty Images)

Parallels are increasingly being drawn between Russia’s unprovoked invasion of Ukraine and the series of events that triggered the Second World War.

Vladimir Putin’s justification for waging war against Kyiv to bring Russian-speakers in the country’s East into Moscow’s orbit has been compared to Adolf Hitler’s demand for self-determination for all German-speaking citizens of the Sudetenland in the late 1930s.

Over the course of six years, from 1 September 1939 to 2 September 1945, upwards of 80 million men and women were killed as war erupted between the Axis and Allied Powers, obliterating much of Europe, Asia and the Pacific.

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Characterised by countless massacres, the Holocaust, civilian bombing, famine and the first deployment of nuclear weapons, the war helped shape international legislation that would dictate the future of global politics. It led to the formation of the United Nations, while also plunging the US and newly formed USSR into a decades-long Cold War.

But how did the war - the most destructive conflict in human history – begin?

‘Seeds sown’ at end of WW1

Most historians agree that the seeds for the second great war of the 20th century were sown at the end of the First World War.

The “War Guilt Clause” of the Treaty of Versailles, signed in 1918, held Germany and Austria-Hungary responsible for the entire conflict and imposed crippling financial sanctions, territorial dismemberment and isolation on both powers.

Germany, for example, was forced to demilitarise the Rhineland and abolish its air force.

Some scholars say that the terms of the treaty were unnecessarily harsh and led to mounting anger in Germany in particular over subsequent decades.

But, said the BBC, “it would be a mistake to imagine that the Treaty of Versailles was the direct cause of World War Two”.

The rise of Hitler

Far from having lifelong military aspirations, Hitler had been a painter in his youth and only joined the Bavarian army at the age of 25 after the outbreak of the First World War. He went on to serve primarily as a message runner.

He was decorated twice for bravery, and was injured on two separate occasions – once when he was hit in the thigh by an exploding shell in 1916, and again when he was temporarily blinded by mustard gas towards the end of the war.

The German surrender at the close of the war “left Hitler uprooted and in need of a new focus”, said The Telegraph. He became an intelligence agent in Germany’s much-diminished military and was sent to infiltrate the German Workers’ Party. There he found himself inspired by Anton Drexler’s anti-communist, anti-Jewish doctrine and ended up developing his own strain of anti-Semitism.

In September 1919 he published his first comment on the “Jewish Question”, stating that the “ultimate goal must definitely be the removal of the Jews altogether”.

Adoption of swastika

Gradually Hitler began to rise through the ranks of the German Workers’ Party, eventually renaming it the National Socialist German Workers’ Party which adopted the swastika as its emblem.

He won broad public support, attracted large donations and developed a reputation as a potent orator. “He found a willing audience for his views that the Jews were to blame for Germany’s political instability and economic woes,” The Telegraph said.

Throughout the following decade, he climbed the ladder of German politics, eventually becoming chancellor in 1933 following a series of electoral victories by his fledgling Nazi Party. When the president, Paul Von Hindenburg, died, Hitler appointed himself Führer – the supreme commander of every Nazi paramilitary organisation in the country.

Hitler denounced the Treaty of Versailles, mounting furious attacks on the unfair terms of the settlement. The treaty incensed Germans, but it had not managed to contain Germany’s potential, and by the mid-1930s the country was surrounded by weak, divided states. “This offered a golden opportunity for Germany to make a second bid for European domination,” said the BBC.

Events of 1939

Throughout the 1930s, several events conspired to push the world back to the brink of war. The Spanish Civil War, the Anschluss (annexation) of Austria, the occupation of the Sudetenland and the subsequent invasion of Czechoslovakia all became key components of the potent tinderbox that was Europe in the late 1930s.

The immediate cause of the Second World War was the German invasion of Poland on 1 September. The invasion was to become the model for how Germany waged war over the course of the next six years, said, with a tactic that would become known as the “blitzkrieg” strategy.

“This was characterised by extensive bombing early on to destroy the enemy’s air capacity, railroads, communication lines, and munitions dumps, followed by a massive land invasion with overwhelming numbers of troops, tanks, and artillery,” the history site said. “Once the German forces had ploughed their way through, devastating a swath of territory, infantry moved in, picking off any remaining resistance.”

Germany’s vastly superior military technology, coupled with Poland’s catastrophic early strategic miscalculations, meant Hitler was able to claim a swift victory.

Appeasement strategy

The Nazi leader had been confident the invasion would be successful for two important reasons, said the BBC. “First, he was convinced that the deployment of the world’s first armoured corps would swiftly defeat the Polish armed forces” and “second, he judged the British and French prime ministers, Neville Chamberlain and Edouard Daladier, to be weak, indecisive leaders who would opt for a peace settlement rather than war.”

Neville Chamberlain has been much derided by many historians for his stance on Nazi Germany, offering, as he did, numerous opportunities for Hitler to honour his commitments and curb his expansionist ambitions. In hindsight, the “appeasement” policy looks absurdly hopeful, but, as William Rees-Mogg argued in The Times in 2009, “at the time there seemed to be a realistic chance of peace”.

After the invasion of Poland, that chance began to look slimmer and slimmer, and Chamberlain determined that it was no longer possible to stand by while the situation on the continent continued to deteriorate. Britain and France declared war on Germany two days after Germany entered Poland but, slow to mobilise, they provided little in the way of concrete support to their ally, which crumbled in the face of Germany’s lightning war.

Decades later, in February 2022, as Putin amassed troops and tanks to the borders and recognised two Russian-backed separatist regions in eastern Ukraine as independent, Ukrainian President Volodymyr Zelenskyy accused the West of pursuing similar appeasement tactics.

And, three weeks later, following a Russian strike on a building in the Obolon district of Kyiv in the early hours of Tuesday morning, one shaken resident echoed Zelenskyy’s criticism, telling Sky News: “This is the result of appeasement.”

Now, with US intelligence officials warning that China is planning to provide financial and military aid to a nuclear armed Russia, the fear of a conflict that drags in the world’s superpowers is back on the agenda.

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