Wikipedia
Denmark–Norway ( Danish and Norwegian: ) was a political entity consisting of the united kingdoms of Denmark and Norway, including overseas Norwegian dependencies of Iceland, Greenland, and the Faroe Islands.
Norway was an influential kingdom of Europe until the mid-14th century, when the Black Plague killed more than half the population. This forced Norway into a personal union with Denmark, which later formed the Kalmar Union with Sweden. Following the departure of Sweden from the Kalmar Union and its dissolution, in 1524 Denmark and Norway entered into a personal union under Danish hegemony, due to Norway's weakened position after the Plague. In 1536 the Kingdom of Norway was integrated into Denmark, and as a consequence its Council of the Realm was abolished. However, Norway continued to have separate institutions and its own laws.The union's most important political institutions and monumental palaces were built in Denmark, strategically in order to restrain Norway from rising to great power as possessed during the Viking Age. Norway was re-established as a kingdom in 1660 after the introduction of absolutism.
The personal union of the two kingdoms lasted until 1814, when the victorious powers of the Napoleonic wars forced the king of Denmark–Norway to cede Norway to Sweden; Norway however resisted the attempt, but was forced to accept another personal union with Sweden on relatively equal terms after a short war with no winner. The Dano-Norwegian union had a lasting impact on Norway which maintained its cultural ties with Denmark. Throughout its union with Sweden, Norway used the Danish written language which descended from Old East Norse instead of Classical Norwegian or Old West Norse.
The corresponding adjective and demonym is "Dano-Norwegian".