World War II

World War II, or the Second World War (often abbreviated as WWII or WW2), was a global war that occurred between September 1939 and May 1945. It involved several nations and their colonies, divided basically between two sides: the Allies and the Axis. More than 100 million people served in military units on both sides.

The Axis
Major Axis nations were Germany, Italy and Japan. Other nations allied to the axis at some point in the war were Hungary, Bulgaria, Romania and Finland. Some nations also had fighters fighting for the axis on a voluntary basis as was the case of the Spanish legion, the Cossacks and other troops who came to enlist in the Waffen-SS. Other states were created as client or puppet states, like Manchukuo (northern China), the Italian Social Republic (after the surrender of Italy 1943–45), Croatia (1941–45) and Slovakia.

The Allies
The major allied nations were the British Empire, France, Soviet Union (from 1941) and the United States (from December 1941). Many other nations joined the allies as was the case of Poland, Canada, Australia, New Zealand, South Africa, Yugoslavia (from 1941), Greece (from 1940), Norway (from 1940), the Netherlands (from 1940), Belgium (from 1940), Czechoslovakia and Brazil (from 1942). China sided with the allies when World War II started, as the country had been at war with Japan since 1937.

The Revision of the Treaty of Versailles
In March 1935, Hitler announced conscription in violation of the Versailles Treaty, and a year later, in March 1936, German forces occupied the Rhineland in violation of the Treaty of Locarno.

Proclamation of the Roman-Berlin Axis
In November 1936, Benito Mussolini proclaimed the Rome-Berlin Axis.

The Spanish Civil War
In the spring of 1936 it became evident that a conflict between the forces of right and the government forming a left coalition called the Popular Front. On July 17-19, Francisco Franco proclaimed revolution in Morocco. It was the beginning of the Spanish Civil War, which lasted nearly three years. In late July, German and Italian planes began the airlift Franco's army who was in Morocco to southern Spain. The British and French decided by non-intervention. The Soviets supported the Popular Front as the Germans and Italians supported the nationalist forces, including bombings in Madrid. In 1936, the primary objective of the Nationalists was Madrid, the Spanish capital. On 28 September, the Nationalists obtained a resounding propaganda victory by lifting the siege of Toledo. The battle for Madrid lasted 5 months and would see the first serious defeat for the Franco forces.

Nazi persecution of Jews
In October 1938, Jews of Polish origin were expelled from German soil. In November 1938 the Germans staged the Kristallnacht purge, the "night of glass" attacking Jewish homes, shops, offices and synagogues in both Germany and Austria. This organized and systematic pogrom was ostensibly an act of retaliation for the assassination of a German diplomat in Paris by a young Jew. About 7,500 Jewish business were destroyed.

Munich agreement
On October 1, 1938, due to the Munich agreement, made by the four nations of Germany, Britain, France and Italy, Hitler´s army occupied the Sudetenland, the border region of Czechoslovakia whose population was German-speaking.

The Treaty of Non-Aggression between Germany and the Soviet Union
On August 23, 1939, Germany and the Soviet Union sign a treaty of non-aggression also known as the Molotov-Ribbentrop Pact. This was a non-aggression pact between the parties. By signing this pact, Hitler intended to avoid a fight on two fronts as had happened in the First World War.

Invasion of Poland
On September 1, 1939 the German army invaded Poland. Two days later Britain and France declared war on Germany. The Germans simulated a false attack from Polish partisans as an excuse to attack. At 4:45 a.m. in the morning, five corps of Hitler's army, backed by the Luftwaffe, invaded Poland soon after Schleswig-Holstein school-battleship opened fire on the fort in Westerplatte in Danzig.

The Russo-Finish Conflict
Between 1939 and 1940 the Soviet Union, after occupying Poland in 1939, invaded Finland. Stalin demanded the annexation of thousands of square miles of original Finnish territory and basing rights to the port of Hango in southern Finland. The Soviets had several setbacks despite overwhelming superiority in troops. In the battle of Suomussalmi two Soviet divisions were massacred. Several factors contributed to the poor campaign of the Red Army. The action of the Soviet armored was not significant and the Finns attacked them quickly with magnetic charges, grenades and Molotov cocktails. The purge of Soviet officers by Stalin was another contributing factor. With the arrival of Timoshenko, the Soviet units imposed their superiority. The peace treaty was signed in March 1940 with territorial losses imposed on the Finns, but not for long. After the invasion of the Soviet Union, the Finns fought a war in order to further restore the borders which existed before the Soviet invasion.

Battle for Berlin
By the first days of February 1945 the Soviets reached the Oder river. In the south, in early March 1945, the Germans attempted a final offensive to recapture Budapest, but without success. The Soviets had already captured Silesia and Pomerania in late March 1945.