| YEAR | DATE | EVENT | HEAD OF STATE |
| 1289 | Duchy - dinasty Brunswick-Este | duke Alberto II | |
| 1318 | duke Ottone II duke of Brunswick | ||
| 1344 | duke Ernesto | ||
| 1367 | duke Ottone II | ||
| 1394 | duke Ottone III | ||
| 1463 | duke Guglielmo I duke of Brunswick | ||
| 1482 | duke Guglielmo II | ||
| 1503 | duke Erik I | ||
| 1540 | duke Erik II | ||
| 1584 | duke Giuglio | ||
| 1589 | Union to Duchy of Brunswick-Kalenberg |