it is goood that you specified India and Europe - because when saying overseas I think of the Americas first ...
If you consider only acceptance (and not miles/points/insurance/service etc), than in Europe it is:
1) Mastercard/Eurocard
2) VISA
3) Northern and Central Europe: Diners; Southern Europe: American Express
4) Northern and Central Europe: American Express; Southern Europe: Diners
[This message has been edited by Rudi (edited 12-12-1999).]