| Type | Duchy |
| Rulers | Various Danish lineages |
| Location | Northern France and England |
| Religion | |
| Government | Feudalistic monarchy |
| Notable for | Naval prowess • Scientific advancement • Cultural achievement • Close ties with England |
| War periods | Hundred Years War • Multiple other wars |
| Capital city | Rouen |
| Official language | |
| Period of existence | 11th to 17th centuries |
