Formal relations between Siam and the Vatican date to 1669 when Pope Clement IX sent a papal brief to King Narai. Informal relations began earlier with the arrival of the Portuguese and their priests. King Narai responded to the overtures of the Holy See with two missions to Rome but only the second arrived at the end of 1688. The dramatic events behind these missions are related by well-known historian, Michael Smithies, assisted by the former Apostolic Nuncio of Bangkok, Mgr. Bressan, now Archbishop of Trento.