| 2014-07-01 | Association merger converted to a simple merger | 53020 → 53127 | La Baroche-Gondouin → Lassay-les-Châteaux |
| 2014-07-01 | Association merger converted to a simple merger | 53127 | Lassay-les-Châteaux |
| 2014-07-01 | Association merger converted to a simple merger | 53149 → 53127 | Melleray-la-Vallée → Lassay-les-Châteaux |
| 2014-07-01 | Association merger converted to a simple merger | 53166 → 53127 | Niort-la-Fontaine → Lassay-les-Châteaux |
| 1974-10-01 | Association merger | 53127 | Lassay-les-Châteaux |
| 1974-10-01 | Association merger | 53166 → 53127 | Niort-la-Fontaine → Lassay-les-Châteaux |
| 1973-01-01 | Deletion | 53127 | Lassay |
| 1973-01-01 | Association merger | 53020 → 53127 | La Baroche-Gondouin → Lassay-les-Châteaux |
| 1973-01-01 | Association merger | 53127 | Lassay → Lassay-les-Châteaux |
| 1973-01-01 | Association merger | 53149 → 53127 | Melleray-la-Vallée → Lassay-les-Châteaux |
| 1966-01-01 | Simple merger | 53081 → 53127 | Courberie → Lassay |
| 1966-01-01 | Simple merger | 53127 | Lassay |
| 1943-01-01 | Creation | 53127 | Lassay |