Why Did War Break Out In 1939?
There wasn't just one main cause or reason for the outbreak of war in 1939. In fact, it was the build up of many different factors that led to the Second World War. The following are the factors that led to war:
The rearmament of Germany
German rearmament began after Hitler left the 1932-34 Geneva Disarmament Conference. He stated that as the victors of WWI would not disarm to his level, he would rearm Germany to their level. By 1935 rearmament was well underway. This involved conscription and munitions factories.
Rearmament alarmed the French who, feeling insecure, reinforced the Maginot line (built between 1929 and 1934). This line of steel and concrete fortifications stretched from Belgium to Switzerland. Because Germany would be able to avoid it and invade France via Belgium, France remained passive without Britain's support.
Britain was sympathetic towards Germany and even signed an Anglo-German naval Treaty (June 1935) allowing Germany's navy to be 35% of the size of the Royal Navy.
Hitler used his new found arms to support Franco in the Spanish Civil War (1936-9) Hitler sent the Condor Legion of the Luftwaffe to bomb Guernica on the 26th April, 1937. Guernica was completely destroyed and Franco went on to conquer the Basque areas of Spain. Hitler had used Spain as a practise ground.
The remilitarisation of the Rhineland
Having broken the Treaty of Versailles once, Hitler risked doing it a second time by marching 30,000 troops into Cologne on the 7th March 1936. France, with 250,000 troops mobilised, remained passive because Britain would not support her, and so let the remilitarisation take place. Britain took the view that Germany was 'marching into her own back yard.'
To show that his remilitarisation was popular, Hitler held a plebiscite,