At the start of the twentieth century, the atmosphere in Europe was very tense. The major European countries had a complex system of alliances and rivalries, and war was very likely. Germany and the Austro-Hungarian Empire formed the Central Powers while Britain, France and Russia formed a looser alliance known as the Entente.

In the 1800s, the big European countries had colonised many parts of Africa, the Middle East and Asia, to increase their wealth and power. They especially targeted Africa, and by 1900, only 10% of the African continent was not ruled by foreigners. Germany had been united only in 1871, and had started late in colonisation. The German emperor, Kaiser Wilhelm II, wanted to build an empire as big as those of Britain and France. Competition was fierce.

Amidst this tensed background, war broke out with a single incident - the assassination of the Archduke Franz Ferdinand, heir to the Austrian throne.

Read Gunshots Shatter Peace, 1914

Actually, the war was mainly a European war, but it eventually involved so many non-European countries that it became a "World War". Many believed the war would be short and glorious, but it dragged on for four years, killing 17 million people, much more than any previous conflict.

Germans sink Lusitania, 1915

The Battle of Verdun and Battle of Somme, 1916

At the Battle of Marne in Autumn of 1914, the Allies stopped the Germans from advancing further into France. When both sides could not move forward, they dug wide parallel trenches in which they defended themselves. Barbed wire and soldiers with machine guns effectively guarded these trenches, while those wounded could rest and recover in the living area (in the lower part of the trench).

In 1914, Russia declared war on Austria and Germany. However, by the summer of 1915, the war was going badly for the Russian forces. In St. Petersburg, protests broke out in February 1917.

Read The Russian Revolutions, 1917
Read Russia and the First World War

International Tensions:

Pact banning war signed, 1928

Italy embraces Fascism, 1922

Mussolini's Italian Revolution, 1926

Mussolini’s invades Abyssinia (Ethiopia), 1935

Hitler jailed for attempted coup, 1923

Credit Anstalt Bank Collapses, 1931

(Austria and Germany face economic problems)

MacDonald, Roosevelt and Hitler lead, 1932

Hitler builds up his power, 1934

The Nuremberg Laws, 1935

Olympic Triumph for Black American Owens, 1936

Rome-Berlin Axis, 1936

Hitler Absorbs Austria, 1938

Hitler invades Czechoslovakia and Poland, 1939

(The Start of World War II)

During the 1930s, Japan the most developed power in Asia, invaded and conquered parts of nearby countries of Manchuria and China. Japan’s growing power brought it closer to the European nations of Germany and Italy. In 1934, Japan made an anti-Soviet pact with Germany. The three countries eventually formed the Axis Powers who fought the Allies in World War II.

Read Japan invades China, 1937

Hitler invades Czechoslovakia and Poland, 1939

Italy Declares War, 1940

Churchill leads War Effort as British Prime Minister, 1940

Bombing of Pearl Harbour, 1941

USA strikes back in the Pacific, 1942

The Greatest Tank Battle, 1943

Italian Surrender, 1943

D-Day landings break German defences, 1944

Atomic Bomb dropped on Hiroshima and Nagasaki, 1945

(This marks the end of the war)

The Second World War led to advancements in aircraft, flying bombs and weaponry. The sub-machine gun, an automatic light weapon, became widely used because it could be carried and fired by just one man. In the 1930s, both sides developed jet-powered planes that were much more powerful than those powered by propellers.

In 1944, German scientist Wernher von Braun developed the V-1, a flying jet-powered bomb. The following year, the V-2 was built. It was able to hit and destroy a target from a distance of 320km (200 miles). These rockets were launched from German-occupied countries in Europe onto Britain.

By 1939, Britain had a chain of radar stations along its southern and eastern coasts. These used radio waves to detect aircraft up to 160km (100 miles) away. They were important in preventing successful air attacks on Britain.

The atomic bomb, the most powerful weapon the world has known, was used at the end of the war. The death and devastation caused was so horrific that it has never been used again in a war since. The fear of nuclear war has dominated politics in the second half of the twentieth century.

Read The US Marches into North Korea, 1950
Read The Korean War Ends, 1953

After Vietnam became independent of France in 1954, the communist North Vietnam, led by Ho Chi Minh, tried to gain control of the South, which had a US-supported dictatorship under Ngo Dinh Diem. Later, the US government sent forces to try to stop the spread of communism and the conflict developed into a full-scale war.

Read The United States and the Vietnam War, 1965

Dentente
The superpowers saw that waging a constant, undeclared war was harmful, especially with the development of nuclear weapons. During the 1970s, there was an easing of tension known as dentente. In the 1980s, despite continued general distrust and military alertness between USA and the USSR, a friendlier relationship began to develop.