Regensburg

Holy Roman Empire de facto · 1789 – August 6, 1806 (from the border data)
Confederation of the Rhine de facto · April 11, 1807 – November 4, 1813 (from the border data)
Kingdom of Bavaria de facto · June 30, 1810 – June 3, 1814 (from the border data)
German Confederation de facto · June 8, 1815 – May 18, 1848 (from the border data)
Kingdom of Bavaria de facto · May 1, 1816 – May 4, 1871 (from the border data)
German Confederation de facto · November 29, 1850 – August 23, 1866 (from the border data)
German Empire de facto · May 5, 1871 – November 9, 1918 (from the border data)
Germany de facto · November 11, 1918 – May 8, 1945 (from the border data)
Germany de facto · since May 23, 1949 (from the border data)