This Dec 25 is the day Jesus Christ was given birth to the earth. He is definitely the person who has most changed world history. Only about 30 years he had lived, only about 3 years he had missioned, however after his passing away his activity has affected later world history so enormously. Not he in history, there must not been the prosperities of Roma and Franc empire, Crusaders, Renaissance, discoveries of new world and so on, even in Japan capital must have been located at elsewhere except Tokyo. Some historian might insist we should not discuss cases another story had been evolved, however I think it important we consider significances about big event or great persons.