Union badge of Norway and Sweden

The union mark of Norway and Sweden (Swedish: unionsmärket or unionstecknet, Norwegian: unionsmerket) was a symbol of the Union between Sweden and Norway. It was inserted into the canton of the Swedish and Norwegian national flags from 1844 to denote the partnership of the two countries in a personal union. The mark combined the flag colours of both kingdoms, equally distributed, to reflect their equal status within the union. The stand-alone design of the mark was used for the diplomatic flag and the naval jack of the union. The union mark remained part of the flags of both countries until it was removed from the merchant and state flags of Norway in 1899 because of increasing Norwegian dissatisfaction with the union. It remained on the naval ensign of Norway and all Swedish flags until the dissolution of the union between Norway and Sweden in 1905.

The Union of Sweden and Norway came about as a result of the Napoleonic Wars, when the king of Denmark-Norway, on the losing side, was forced to cede Norway to the king of Sweden by the Treaty of Kiel in 1814. Norwegian resistance led to the declaration of national independence and the adoption of a constitution on 17 May 1814. A brief war with Sweden resulted in the Convention of Moss on 14 August 1814 and the Norwegian constitutional revision of 4 November 1814 to open the way for a personal union. On the same day, the Norwegian parliament chose to elect Charles XIII of Sweden as King of Norway.

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