Christianity, filtered through the heritage of Enlightenment, is a founding stone of European identity. Western Christianity is of particular importance here, as only in the region it dominated we can speak of Enlightenment and periods that precede it, that is Renaissance and Reformation. European Union is primarily constituted by countries that are culturally related to Western (Latin) Christianity. Enlightenment (secular rationalism) as such was not sufficient for creation of European identity. The paper describes the evolution of European identity closely linked with Christianity, that was later on left for rationalism and national identities. I try to prove that the identity of Europeans is historically closely linked to the diversity of nations that constitute Europe and that a national identity serves to underline European Community rather than deny it. Existing European identity has its roots in common history, contrary to popular believes that Europeans identify only with their nations. The paper also explains why new European identity needs to be constructed in relation to common European past and not in relation to the future of Europe.