| YEAR | DATE | EVENT | HEAD OF STATE |
| 1195 | Duchy - dinasty Brunswick-Este | duke Guglielmo I | |
| 1213 | duke Ottone I | ||
| 1252 | duke Alberto I | ||
| 1279 | duke Enrico I | ||
| 1292 | duke Alberto I | ||
| 1318 | duke Ottone II | ||
| 1344 | duke Magnus I | ||
| 1369 | duke Magnus II | ||
| 1373 | duke Bernardo I | ||
| 1213 | duke Guglielmo II | ||
| 1482 | Union to Duchy of Brunswick-Luneburg |