whats best to study havent a clue about international relations in the twentieth centuary :L
International relations consists of...
*Results of WW1 / Treaty of Versailles
*Dictators (Hitler, Mussolini) / Pre-WW2
*WW2 and Holocaust
Make sure you know 1/3 of the Cold War crisis's cause they come up often and didn't come up last year so they probably will this year. WW2 is very important. Those are the 2 most important topics. Look at the past exam papers and see which essays have come up. Common ones are Battle of Britain, Holocaust, D-Day landings etc.
A crisis came up last in the cold war as a PIH so may come up on section 6 this year
Mussolini is being backed to come up in 2014
Do you mean as a long question
As part of Q6 International Relations