the site of the first european missionary activity was the principal city of
Early centers of Christianity Thessaloniki, the major northern Greek city where it is believed Christianity was founded by Paul, thus an Apostolic See, and the surrounding regions of Macedonia, Western and Eastern Thrace, and Epirus, which also extend into the neighboring Balkan states of Albania and Bulgaria, were early centers of Christianity. Of note are Paul's Epistles to the Thessalonians and to Philippi, which is often considered the first contact of Christianity with Europe.[38] The Apostolic Father Polycarp wrote a letter to the Philippians, c.125.