Roman Catholic Archdiocese of Cologne Roman Catholic Archdiocese of Cologne The Archdiocese of Cologne (; ) is an archdiocese of the Catholic Church in western North Rhine-Westphalia and northern Rhineland-Palatinate in Germany. The Electorate of Cologne—not to be confused with the larger Archdiocese of Cologne—was one of the major ecclesiastical principalities of the Holy Roman Empire. The city of Cologne as such became a free city in 1288 and the archbishop eventually moved his residence from Cologne Cathedral to Bonn to avoid conflicts with the Free City, which escaped his jurisdiction. After 1795, the archbishopric's territories on the left bank of the Rhine were occupied
Electorate of Cologne confused with the Roman Catholic Archdiocese of Cologne, which was larger and included suffragant bishoprics such as Liège and Münster over which the Elector-Archbishop exercised only spiritual authority (see map below). Cologne was the ancient Roman city of Colonia Agrippina in the province of Germania Inferior, and has been a bishop's see since Roman times. In 953, the archbishops of Cologne first gained noteworthy secular power, when Bishop Bruno was appointed as duke by his brother Emperor Otto I. To weaken the secular nobility, who threatened his power, Otto endowed Bruno and his successors in the bishop's see with the