Short answer:

The Swedish-Norwegian Union or Sweden-Norway was a personal union of the two Scandinavian countries Sweden and Norway that existed from 1814 to 1905. It resulted from the Peace of Kiel following the Coalition Wars and the Convention of Moss. The two governments of the countries were based in the capitals of Stockholm and Kristiania (today Oslo), whereby the Norwegian government was bound to the Swedish government in Stockholm, but gained more and more autonomy over time.

Full story:

Peace of Kiel:

From 1813 to 1814, the kingdoms of Sweden and Denmark fought each other during the Coalition Wars. Denmark supported France and thus became the target of Sweden, which had allied itself with Russia, among others, against Napoleon. Sweden attacked Denmark from the south, the latter lost the war and in the Treaty of Kiel or Peace of Kiel, Danish-ruled Norway was ceded to Sweden on 14 January 1814. On 18 January, the Danish King Frederick VI wrote a letter in which he officially released Norway from Denmark, and the Denmark-Norway Union was dissolved. However, Greenland, Iceland and the Faroe Islands, previously Norwegian, belonged to Denmark from then on.

Independence of Norway:

Norway was supported by the Crown Prince of Denmark and Governor of Norway and later Danish King, Christian Frederick (Christian VIII), in resisting and opposing the takeover of Norway by Sweden. At an assembly he convened on 17 May 1814 in Eidsvoll, about 30 km north of Kristiania, the basic Norwegian constitution, which is still in force today, was adopted, granting the country independence from Denmark and Sweden, and the Danish Crown Prince Christian Frederick was designated as King of Norway. The assembly was attended by 112 selected people, including military officers and politicians. About two thirds of the participants were peasants. Of the votes cast by the delegates, 78 were in favour of Norwegian independence with government by a Danish king, only 31 votes were in favour of forming a union with Sweden. 17 May is today's bank holidays of Norway, as it is considered Independence Day.

Foundation of the Union:

On 4 November 1814, the personal union between Sweden and Norway was established. Norway's constitution was only slightly changed when the personal union was founded, due to the convention signed in Moss. Thus, the Swedish king was the head of state in both countries and a common foreign policy was also to be pursued. The supreme commander of the Norwegian army was also the Swedish king, although Norway's armed forces could only be deployed outside Norway with the consent of the Norwegian government. Norway's interests within the Union were represented by the Norwegian Parliament (Storting) and the government, which had its seat in Kristiania and a branch office in Stockholm. With the formation of the personal union, Norway gained almost total independence through the new constitution.

This almost total independence, which was unprecedented for the Kingdom of Norway, marked the beginning of the creation of an independent, "proper" Norwegian culture based on the people's existing identity from the centuries before the union with Sweden. A real national consciousness was formed over time by, among others, well-known Norwegian artists and writers as well as musicians from Norway. This also gave rise to the idea of a new written Norwegian language. The so-called Nynorsk (German: Neunorwegisch), created at the time of the Swedish-Norwegian Union, is used by many Norwegians today and is the official language of Norway.

In the post-war period, which was also the initial period of the personal union, Norway was severely weakened economically. There was severe inflation, as money had been printed en masse to finance the war. Norwegian money was initially worth only a fifteenth compared to the years before the war. It was not until the 1830s that the country recovered from the crisis, especially the timber trade with Great Britain flourished and the merchant fleet increased considerably. By the end of the 19th century, it was the largest merchant fleet in the world after the British and US fleets.

In the 1870s and 1880s, Norway's relationship with Sweden deteriorated as the Norwegian Parliament wanted to introduce constitutional amendments three times (1874,1879 and 1880) that would have ensured that governments in Norway could only continue to rule with the support of the National Assembly. The proposals were aimed at parliamentarism, which displeased the then King of Sweden-Norway, Oskar II. Each time he refused to sign the motions.

In 1884, Oskar II gave in, signed an amendment to the Norwegian constitution and appointed the Liberal leader, Johan Sverdrup, as Norway's first prime minister. From then on, the Storting had the decision on Norway's government. Parliamentarism was established and Norway became the first Scandinavian country to be governed by parliament. The first political parties were formed in this year, and about a year later male suffrage was introduced in Norway.

Norway was independent in domestic politics, but foreign policy continued to be determined from Sweden, which is why the question of a separate Norwegian consular service arose and the Storting decided to introduce foreign policy offices for Norway. However, this was rejected by the Swedish government in 1892 and the elected Norwegian government tried to enforce the resolutions against permission. Sweden then threatened military action and, after subsequent negotiations, agreed to accommodate the Norwegian government further. However, the ideas of Sweden and Norway on further Norwegian autonomy were still so different that there could be no good compromise. Negotiations on fundamental political issues concerning Norway's ties to Sweden failed in 1898. In that year, Norway demonstrated its independence by banning the Union emblem from its own trade flag, despite the Swedish crown's refusal.

After renewed negotiations on Norway's position in the Union, which also failed, the Norwegian government led by Christian Michelsen resigned. The then King of Sweden-Norway, Oskar II, no longer had the power to appoint the government in Norway, which now had to be elected by those eligible to vote. On 7 June 1905, the Storting declared the union with Sweden dissolved, as the King was no longer acting as Norwegian King. The Swedish government refused to give Norway total independence, threatened military action and forces were mobilised on both sides. Negotiations of the terms of Norway's withdrawal from the Union between Sweden and Norway began. On 13 August, in a referendum demanded by Sweden, 368,392 voters voted to abandon the Union and give Norway absolute independence, with only 184 votes against.

On 23 September 1905 in Karlstad, Sweden, the two countries finally agreed in a convention on requirements to be fulfilled, such as an arbitration treaty or regulations concerning transit trade. The so-called Treaty of Karlstad was approved by the Storting on 9 October 1905 by 101 votes to 16, and unanimously by the Swedish Parliament on 13 October. On 26 October 1905, the treaty became legally binding with the signatures of representatives of both kingdoms, and the union between Sweden and Norway was officially dissolved.

In Norway, which was now a fully independent country, the Storting elected the Danish Prince Carl of Denmark and Iceland, renamed Haakon VII, as the new king. On 25 November 1905, Haakon VII ascended the throne in Kristiania.

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