Diocese of Siret

Siret was one of the more stable Latin bishoprics founded in medieval Moldavia.

Since the 13th century, missionaries of the mendicant orders, Franciscans and Dominicans, created several Latin Catholic communities in present Romania, for whom the Holy See decided to created bishoprics, south and east of the Carpathians (in Walachia and Moldavia), generally short-lived, like the Diocese of Siret / Seret / Cereten(sis) (Latin adjective), established in 1371.

Catholicism was on the rise among the traditionally Orthodox population due to the political late 14th century context, as the Ottoman advance, nearly encircling the imperial capital Constantinople (conquering (H)Adrianopolis, now Edirne, in 1360), the Byzantine emperors sought a political and hopefully military ally in the Catholic west, which had crusaded against Islam to and in the Middle East before.

Similarly in Moldavia, where Bogdan I obtained virtual independence in 1359 as founding voivode (autonomous prince), seeking aid and protection from Poland, welcomed Latin missionaries, Franciscan Friars Minor (founding a monastery at Siret in 1340) and Dominicans.

Bogdan's son and indirect successor Lațcu of Moldavia (1365-1373) invited a delegation from Rome, promising his and the people's conversion to Catholicism and asked Pope Urban V to send missionaries and erect a Latin diocese in his principality's capital, Siret. On 24 July 1370 the Pope instructed the archbishop of Prague and bishops of Bratislava and Kraków (Cracovia) to verify/complete the sincerity of Laţcu (although his wife remained Orthodox) and mandated them to erect such diocese covering the Moldavian state. Pope Gregory XI established it in 1371, exempt (i.e. directly subject to theHoly See); Polish Franciscan Andrzej Jastrzebiec was consecrated first Bishop by archbishop Florian of Cracovia. The cathedral, dedicated to John the Baptist, was built by queen Margareth, Catholic kin of the Hungarian royal family, which in 1377 had invited Dominicans to Siret.

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Wikipedia