(a) Three causes of the First World War (1914): 

Militant Nationalism and Mutual Rivalries: Each nation thought about` her own national interest. Nationalism had become competitive and aggressive. The spirit of Nationalism was a strong driving force in European politics of the 19th century. Thus the whole atmosphere was charged with narrow militant nationalism and inter-state rivalries. 

Europe Divided into Power Blocs: In Europe, there existed single nation states like France, Holland, Germany. There also existed some imperial states like Austria Hungarians empire, which included nationalities like Serbs, Hungarians, Bosanions and the Croats. There was the Russia empire which included Polish Ukranian, Turkish and Mages people. Great Britain was also a colonial empire. The major European nation were divided into two Bloc’s. Germany, Austria, Hungary and Italy had made the Triple Alliance in 1882 A.D. and the Dual Alliance united France and Russia. At the dawn of the 20th Century Europe was divided into two hostile camps. Tension prevailed in their relations with each other, bloc-wise. The immediate cause: The Sarajevo Incident: In June 1914, The Archduke Francis Ferdinand, The Heir-Apparent to the throne of Austria went to Sarajevo, the Capital of Bosnia, on an official visit. On June 28, 1914, he and his wife were shot dead. The assassin, Gavrilo Princep, was a nineteen years old Bosnian student. This dual murder had been planned in Serbia by a secret society of patriotic terrorists called the “Black hand”. The Austrians blamed the Serbians for this crime, as the assassin and fellow conspirators had received their guns and bombs in Serbian Capital with the help of Serbian officials. 

(b) Three clauses of the Treaty of Versailles are as follows: 

1. The Treaty declared Germany guilty of aggression. She had to pay a very heavy sum estimated of 33 billion dollars as war indemnity to the allies. Germany was to evacuate the places she had captured during the war. 

2. The area of the Rhine Valley was to be demilitarised. Germany could not maintain or construct any fortification either on the left bank of the Rhine or on the right bank. Moreover, all existing fortifications were required to be destroyed. To guarantee the execution of the Treaty, the German territory west of Rhine was to be occupied by the Allied troops for 15 years. 

3. The German army was dishanded. She was allowed to keep only one lakh soldiers. The air force and sub-marines were also banned. Her navy was limited to 15,000 men and 36 ships. 

(c) The Peace Settlement at Paris was made in a spirit of revenge. The Germans felt that too much injustice had been done to them. The victorious powers had deprived Germany of huge tracts of its territory. She was burdened with an immense War Indemnity. It was impossible for a pround German race to forget the consequences of the War, which they had lost so humiliatingly. This fuelled the rise of Nazism in Germany and entered upon a career of aggression.