Roman Catholic Archdiocese of Gniezno

The Archdiocese of Gniezno is the oldest Latin Catholic archdiocese in Poland, located in the city of Gniezno. The ecclesiastical province comprises the suffragan dioceses of Bydgoszcz and Włocławek.

The Metropolitan Archdiocese of Gniezno was established in 1000 AD on the initiative of the Polish duke Bolesław I the Brave. He had the relics of the missionary and martyr Adalbert of Prague transferred to Gniezno Cathedral, which soon became a major pilgrimage site. Here Bolesław met with Emperor Otto III in the Congress of Gniezno, where the duke obtained investiture rights and created the Gniezno archbishopric, superseding the older Diocese of Poznań. Led by Adalbert's half-brother Radim Gaudentius, the ecclesiastical province then comprised the suffragan dioceses in Kraków, Wrocław, and Kołobrzeg , and from about 1075 also Poznań.

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