Russia's change of ideology to communism would prove to be one of the most provident causes of the Cold War because this led to a bigger severance between Western Europe and Russia. The West took it as an act of treachery which then convinced them that Russia was untrustworthy. Lenin had also established the Cheka, a secret force which brutally crushed out any opposition which had a different ideology. The new Bolshevik Government had also signed a ceasefire treaty with Germany and negotiated a peace-treaty, The treaty of Brest-Litovsk. Russia's allies, the French and British, felt betrayal from Russia as they backed out from the war. Russia's measures seemed selfish to their allies but they had their reasons. They suffered the most casualties out of all the countries with a total of 6 million soldiers, killed or injured. If the West had realized this, the outcome could have been completely different. Therefore The West were also responsible to create the tension between Russia.
The emergence of Adolf Hitler in the 1930s signaled the arrival of a new threat to peace in Europe. Adolf Hitler was a German dictator who formed a far right German political system that was known as Nazism. Many of the personal beliefs he was implementing to the German population were very extremist and due to this his presence in Europe was peace threatening at the time. Hitler was particularly a great threat to Russia as he too despised Communism. According to Hitler, Communism was a Jewish political strategy to conquer Germany and the rest of the world and for this reason he hated Communism and Jews with a passion. He had come to this notion because he examined the high officials in the Communist government and he noticed that a number of them had Jewish Heritage. He made a link between these two and claimed that this was a conspiracy led by the Jews. This was false and at the face of this new threat, Russia quickly realized its 'allies' were in no rush to help them contain Hitler and his new system of Nazism as no attempt was made by the Western governments of France and Britain to co-operate with Russia to stop it.