He is not anymore. He renounced that title to become a British citizen. He was a Greek prince though because he was born in Greece into the Royal Family.
The answer to your question is yes and no. Yes, he was born in Greece and he was born a Prince of Greece and Denmark. This however does not tell the whole story. He does not have any Greek ancestry...
I am answering this presuming that you are referring to the current Prince Phillip of England, husband of Queen Elizabeth II. Prince Phillip is by birth a Prince in Greece and Denmark, but when he...