This list refers to the Roman Catholic dioceses and ecclesiastical provinces in Germany and the organisational changes between 1821 and 1994. The territorial changes through and after the Napoleonic Wars determined much of today's diocesan boundaries. The territorial changes after the World Wars were followed by new diocesan boundaries in the 1920s and 1970s. Internal reorganisations took place in the 1930s, 1950s and early 1990s.

Fulda Conference of Bishops

This conference, preceding today's Conference of German Bishops, was established as Würzburg Conference of Bishops (only 1848) and as a regular institution named Fulda Conference since 1867. Renamed into German Bishops' Conference in 1965.

List of Catholic dioceses in Germany between 1821 and 1993

Ecclesiastical Province of Bamberg

This ecclesiastical province was founded in 1818.

List of Catholic dioceses in Germany between 1821 and 1993

Archdiocese of Bamberg

Diocese of Eichstätt

Diocese of Speyer

Diocese of Würzburg

Eastern German Ecclesiastical Province

This ecclesiastical province emerged in 1930 and was dissolved in 1972. Diocesan areas east of the Oder-Neiße line were under apostolic administration by Polish clergy since 1945. Archdiocese of Breslau (Wrocław), since 1930, partially under Polish apostolic administration 1945–1972, then East German part dissected and the rest part of Polish episcopate Diocese of Berlin, est. 1930, partially under Polish apostolic administration 1945–1972, then Polish diocesan area dissected Diocese of Ermland (Warmia), since 1930, under Polish apostolic administration 1945–1972, then part of Polish episcopate Prelature of Schneidemühl (Piła), est. 1930, under Polish apostolic administration since 1945, dissolved in 1972

List of Catholic dioceses in Germany between 1821 and 1993

Ecclesiastical Province of Gnesen-Posen

This historically Polish ecclesiastical province was made part of the Fulda Conference in 1821 and disentangled in 1918/1919. to join the Episcopal Conference of Poland

Archdiocese of Gnesen (Gniezno), in personal union with the Diocese of Posen (Poznań) Diocese of Culm (Chełmno), to Poland in 1920, Apostolic Administration of Tütz (Tuczno) - the parts of the abovementioned dioceses which remained with Germany 1920–1923, then disentangled to form together the Territorial Prelature of Schneidemühl (Piła), subordinate to Archdiocese of Breslau (Wrocław) Apostolic Administration of the Free City of Danzig - later the exempt Diocese of Danzig (Gdańsk)

Middle German Ecclesiastical Province

Archdiocese of Paderborn, since 1930

Diocese of Fulda, since 1930

Diocese of Hildesheim, 1930–1994, then part of the Ecclesiastical Province of Hamburg

Ecclesiastical Province of Munich and Freising

This ecclesiastical province was founded in 1821.

Archdiocese of Munich and Freising

Diocese of Augsburg

Diocese of Passau

Diocese of Regensburg

Rhenish Ecclesiastical Province

This ecclesiastical province was founded in 802, it is also called ecclesiastical province of Cologne.

Archdiocese of Cologne, newly Belgian Eupen-Malmedy dissected in 1921

Diocese of Aachen, est. 1930

Diocese of Essen, est. 1958

Diocese of Münster

Diocese of Osnabrück, 1930–1994, then part of the Ecclesiastical Province of Hamburg Diocese of Paderborn, elevated to metropolia of the Middle German Ecclesiastical Province in 1930 Diocese of Trier

Upper Rhenish Ecclesiastical Province

This ecclesiastical province was founded in 1821, it is also called ecclesiastical province of Freiburg im Breisgau.