| YEAR | DATE | EVENT | HEAD OF STATE |
| 1432 | Duchy - dinasty Brunswick-Este | duke Guglielmo I | |
| 1482 | duke Federico II | ||
| 1495 | duke Erik I | ||
| 1540 | duke Erik II | ||
| 1584 | duke Giulio duke of Gottinga | ||
| 1589 | duke Enrico Giulio duke of Brunswick | ||
| 1613 | duke Federico Ulrico duke of Grubenhagen | ||
| 1635 | duke Augusto | ||
| 1636 | duke Giorgio | ||
| 1641 | Union to Duchy of Brunswik-Luneburg | ||
| 1665 | Union to Duchy of Brunswik-Grubenhagen | ||
| 1679 | duke Ernesto Augusto I p.e. of Hannover | ||
| 1692 | Union to Principality Electoral of Hannover |