BREMA-AMBURGO, ANTICA DIOCESI di. - In the year 780 Charlemagne entrusted the region between the Elbe, the city of Norden, and the banks of the lower Weser to the Anglo-Saxon missionary Willehad. Willehad was consecrated bishop of B. in 787; his successors were Willeric and Leuderic; B. was then a suffragan diocese of Cologne. On 1 October 847, at the provincial synod of Mainz, the diocese of B. was united with that of A., and St. Anscario became its first archbishop; the city of A. had been founded by Charlemagne in the year 811.
The separation of B. from the metropolitan see of Cologne caused dissensions that ended at the beginning of the 10th century through the intervention of Pope Sergius III. The two Chapters of B. and A. joined together for the election of the archbishop. B. became a missionary center for the countries of northern Europe; like St. Anscario before him, Archbishop St. Rimberto traveled in Denmark and Sweden, as did Archbishop
St. Unno, who died in 936 at Birken (Sweden). St. Adaldago established the suffragan dioceses of Schleswig, Ribe, and Aarhus in Denmark. The most flourishing missionary period was during the time of Archbishop Adalbert (1043-1073); in 1104 Pope Paschal II separated the Danish dioceses and created the archdiocese of Lund (Sweden). In the 13th century, especially under Archbishop Gerhard of Lippe (1219-58), the two dioceses of B. and A. were enriched with religious communities: Augustinians, Benedictines, Carthusians, Cistercians, Premonstratensians, and then Dominicans and Franciscans.
Ancient churches of B.: the collegiate church of St. Willehad, St. Stephen, St. Mary, St. Anscario with a tower 97 m. high, and St. Martin. In A.: St. Peter, St. Nicholas, St. James, and St. Catherine. The last archbishop was Christopher of Brunswick, who was unable to oppose the spread of the Lutheran Reformation. Today the territories of B. and A. belong to the diocese of Osnabrück.