ðə tʃˈɜːtʃ fˈɜːst bɪkˌeɪm ɐ kɐθˈiːdɹəl ɪn wˈʌn θˈaʊzənd sˈɛvənhˈʌndɹɪd twˈɛnti θɹˈiː, wˌɛn ðə dɪoʊsˈiːz ʌv vˈɪɪpjˌʊɹɹi vˈɪboːɹɡ nˈaʊ ðə dɪoʊsˈiːz ʌv tˈæmpɚɹˌeɪ mˈuːvd tə pˈoːɹvuː, ˈæftɚ vˈaɪboːɹɡ wʌz sˈiːdᵻd tə ɹˈʌʃə ɪnðə tɹˈiːɾi ʌv nˈɪstæd.
The church first became a cathedral in 1723, when the diocese of Viipuri (Viborg) (now the Diocese of Tampere) moved to Porvoo, after Vyborg was ceded to Russia in the Treaty of Nystad.