1. Treaty of Versailles :
a. According to the treaty, Germany was stamped as an aggressor and levied a huge war indemnity.
b. She had been deprived of several territories which included Alsace and Lorraine.
c. The rich Saar coal mine was given to France for 15 years under free lease license.
d. German army was reduced. All these humiliating terms against Germany resulted in the Second World War.
2. Spirit of Nationalism :
a. The concepts like Germany for Germans, Italy of Italians led to tension.
b. Germany boosted superiority of German race on the earth.
c. When this crossed all limits it assumes alarming proportion.
3. Failure of League of Nations :
a. The big powers which dominated the league of Nations did not obey the terms and conditions of the League.
b. The League failed to prevent the race for the armament and preserving peace.
4. Rise of Japan:
a. Japan emerged as a world power after the first world war and followed the policy of imperialism.
b. It signed Rome-Berlin-Tokyo Axis and sowed the seeds for second world war.
5. Problem of Minorities:
a. After the first world war a number of new nations had been created but the principle of nationality was not followed.
b. Several countries like Poland, Austria and Czechoslovakia were formed by neglecting the interests of the minority groups.These are the causes for the outbreak of second world war.