| YEAR | DATE | EVENT | HEAD OF STATE | |
| 783 | 10 april | Bishopland | Bishop Wiho I | |
| 810 | Bishop Meginhard | |||
| 829 | Bishop Goswin | |||
| 845 | Bishop Gosbert | |||
| 860 | Bishop Egbert | |||
| 887 | Bishop Egilmar | |||
| 906 | Bishop Bernhar | |||
| 919 | Bishop Dodo I | |||
| 949 | Bishop Drogo | |||
| 969 | Bishop Leutholf | |||
| 978 | Bishop Dodo II | |||
| 996 | Bishop Günther | |||
| 1000 | Bishop Wacholf | |||
| 1003 | Bishop Dietmar | |||
| 1023 | Bishop Meginhar | |||
| 1028 | Bishop Gosmar | |||
| 1036 | Bishop Albrich | |||
| 1052 | Bishop Benno I | |||
| 1067 | Bishop Benno II | |||
| 1088 | Bishop Markwart | |||
| 1093 | Bishop Wiho II | |||
| 1101 | Bishop Johann I | |||
| 1109 | Bishop Gottschalk Von Diepholz | |||
| 1119 | Bishop Diethard | |||
| 1137 | Bishop Udo Von Steinfurt | |||
| 1141 | bishop Philipp Von Katzenellenbogen | |||
| 1173 | bishop Arno Von Altena | |||
| 1192 | bishop Gerhard Von Wildeshausen | |||
| 1216 | bishop Adolf Von Tecklenburg | |||
| 1224 | bishop Engelbert I Von Isenburg (I) | |||
| 1226 | bishop Otto I | |||
| 1227 | bishop Konrad I von Veltberg | |||
| 1238 | bishop Engelbert I Von Isenburg (II) | |||
| 1250 | bishop Bruno Von Isenburg | |||
| 1259 | bishop Baldwin Von Russel | |||
| 1265 | bishop Wittekind Von Waldeck | |||
| 1269 | bishop Konrad II Von Rietberg | |||
| 1297 | bishop Ludwig Von Ravensberg | |||
| 1309 | bishop Engelbert II Von Weike | |||
| 1321 | bishop Gottfried Von Arnsberg arcibishop of Brema | |||
| 1349 | bishop Johann II Hud | |||
| 1366 | bishop Melchior Von Braunschweig-Grubenhagen | |||
| 1376 | bishop Dietrich Von Horn | |||
| 1402 | bishop Heinrich Von Holstein | |||
| 1404 | bishop Otto II Von Hoya | |||
| 1424 | bishop Johann III Von Diepholz | |||
| 1437 | bishop Eric I Von Hoya | |||
| 1450 | bishop Albrecht Von Hoya | |||
| 1453 | bishop Rudolf Von Diepholz | |||
| 1455 | bishop Konrad III Von Diepholz | |||
| 1482 | bishop Konrad IV Von Rietberg bishop of Munster | |||
| 1508 | bishop Eric II Von Braunschweig-Luneburg bishop of Munster | |||
| 1532 | bishop Franz Von Waldeck | |||
| 1553 | bishop Johann IV Von Hoya | |||
| 1574 | bishop Heinrich III Von Saxe-Lauenburg | |||
| 1585 | bishop Wilhelm Von Scheniang | |||
| 1585 | bishop Bernhard II Von Waldeck | |||
| 1591 | bishop Philipp Sigismund Von Braunschweig-Luneburg | |||
| 1623 | bishop Eitel Friedrich Von Hohenzollern | |||
| 1625 | bishop Franz Wilhelm Von Wartenberg | |||
| 1634 | bishop Franz Wilhelm Von Wartenberg | |||
| 1648 | Administration of Duchy of Brunswick | |||
| 1661 | bishop Ernst August I Braunschweig-Lüneburg p.e. of Hannover | |||
| 1698 | 14 april | bishop Karl Joseph Ignaz Herzog von Lothringen, p.e. of Trier | ||
| 1716 | 2 march | bishop Ernst August II Herzog von Braunschweig-Lüneburg p.e. of Hannover | ||
| 1728 | 4 november | bishop Clemens Augustv Herzog von Bayern, p.e. of Koln | ||
| 1761 | 6 february | Principality of Elector of Hannover | ||
| 1802 | 10 november | Union to Principality Electoral of Hannover | ||
| 1815 | Principality of King of Hannover | |||
| 1918 | Union tol German State of Lower Saxony |