World War II (1939-1945)
The deadliest conflict in human history, claiming 70-85 million lives. Germany started it, was devastated by it, and was fundamentally transformed by its defeat.
Prelude - Appeasement and Expansion
Between 1933-1939, Hitler systematically dismantled Versailles. Germany rearmed openly from 1935. In 1936 German troops reoccupied the demilitarized Rhineland. In 1938 Germany annexed Austria (Anschluss) without opposition. The Munich Agreement (September 1938) gave Germany the Sudetenland of Czechoslovakia in exchange for promises of no further demands - a policy of appeasement Britain and France desperately wanted to believe. Six months later Hitler occupied the rest of Czechoslovakia. It was clear nothing but force would stop him.
Blitzkrieg - The Lightning War
Germany invaded Poland on September 1, 1939, triggering declarations of war from Britain and France. The Blitzkrieg ("lightning war") combined tanks, motorized infantry, and air support in fast, coordinated attacks that overwhelmed opponents before they could react. Poland fell in six weeks. In May 1940 Germany attacked France through the Ardennes (bypassing the Maginot Line), reaching the English Channel in 10 days. France fell in six weeks. Britain, isolated, refused to make peace.
Operation Barbarossa - The Eastern Front
On June 22, 1941 Germany invaded the USSR with 3.8 million troops in the largest military operation in history. Initial advances were stunning - 3 million Soviet soldiers were captured in the first months. But the USSR did not collapse. Moscow held. The German advance stalled in the Russian winter without adequate supplies. The Battle of Stalingrad (1942-1943) was the turning point: an entire German army group (300,000 men) was encircled and destroyed. From then on Germany was in strategic retreat. The Eastern Front killed roughly 30 million people.
The War in the West - D-Day and Beyond
Allied strategic bombing devastated German cities and industry from 1942. On June 6, 1944 (D-Day), 156,000 Allied troops landed in Normandy in the largest amphibious operation ever mounted. Paris was liberated in August. Germany launched a final counteroffensive in the Ardennes (Battle of the Bulge, December 1944) that briefly pushed back Allied lines but failed. By spring 1945 Soviet forces were in Berlin. Hitler killed himself on April 30, 1945. Germany surrendered unconditionally on May 8 (VE Day).
Germany's Nuclear Program
Germany had brilliant nuclear physicists in the 1930s - but many were Jewish and fled after 1933 (including Einstein, Szilard, Teller, Frisch, and Meitner). The remaining German program was underfunded, led by Werner Heisenberg, and made a critical error: Heisenberg calculated (wrongly) that a uranium bomb would need tonnes of material, making it seem impractical. Meanwhile the Manhattan Project used the correct calculation. Germany never came close to a bomb and surrendered before the issue was decided.
Defeat and Division
Germany's defeat was total: 5.3 million German soldiers killed, millions more in Soviet captivity. German cities were rubble. The country was divided into four occupation zones (USA, UK, France, USSR). Millions of ethnic Germans were expelled from Eastern Europe. The Nuremberg Trials (1945-1946) prosecuted Nazi leadership for war crimes and crimes against humanity - establishing that "following orders" was not a legal defense and laying the foundation for international humanitarian law.