[So I have just received my fifth rejection. What am I doing wrong?]

I have recently graduated from an obscure liberal arts college with a cum Claude in history, minoring in English and Economics. My cumulative GPA was a 3.3 I did abroad programmes at both Oxford and Cambridge. I was also chairman of the campus museum and involved in the debating society.
I am applying for master's programmes in international relations. I have not taken the GRE.

So far, I have not been accepted anywhere. I have been rejected from the following schools:

Cambridge

Edinburgh

St. Andrew's

Toronto

University College, London.

Is there anything I can do differently so I can get accepted somewhere?