It seems tough; only coz of the reason that no book is available for it. But one can prepare for this subject by:

. Microsoft Encarta Encyclopedia; a software encyclopedia easily available in the market
. Google/ wikipedia
. World History; a book by BV Rao

Besides that, some academy notes may be available in Lahore. If some friend is there from Lahore, plz also inform us about that.
n if any friend has any other idea about the subject; plz share