Convention of Moss The Convention of Moss was a cease fire agreement , signed August 14 , 1814 , between the Swedish King and the Norwegian government . It followed the Swedish - Norwegian War due to Norway ' s claim to sovereignty . It also became the " de facto " peace agreement and formed the basis for the personal union between Sweden and Norway that was established when the Norwegian Storting ( Parliament ) elected Charles XIII of Sweden as king of Norway on 4 November 1814 . The Union lasted until Norway declared its dissolution in 1905 . In 1814 , Denmark – Norway was on the losing side in the Napoleonic wars . On January 14 , 1814 , at the Treaty of Kiel , Norway was ceded to the king of Sweden . In an attempt to take control of their destiny the Norwegians convened a constitutional assembly at Eidsvoll and on May 17 , 1814 , signed the Constitution of Norway . The vice - roy and heir to the thrones of Denmark and Norway , prince Christian Frederik , was elected by the assembly as king . The de facto Swedish ruler , crown prince Charles John , acting on behalf of king Charles XIII , rejected the premise of an independent Norway and launched a military campaign on July 2 , 1814 with an attack on the Hvaler islands and the city of Fredrikstad . The Swedish army was superior in numbers , was better equipped and trained , and was led by one of Napoleon ' s foremost generals , the newly elected Swedish crown prince , Charles John — Jean Baptiste Bernadotte . The hostilities opened on 26 July with a swift Swedish naval attack against the Norwegian gunboats at Hvaler . The Norwegian vessels managed to escape , but they did not take part in the rest of the war . The main Swedish thrust came across the border at Halden , bypassing and surrounding the fortress of Fredriksten , and then continuing north , while a second force of 6 , 000 soldiers landed at Kråkerøy outside of Fredrikstad . This town surrendered the next day . This was the start of a pincer movement around the main part of the Norwegian army at Rakkestad . The Norwegian army delivered several offensive blows to the Swedes , thus applying pressure on the Swedes to accept Norway as a sovereign nation , and opening up negotiations . Armistice negotiations concluded at Moss on August 14 , 1814 . In the peace negotiations , Christian Frederik agreed to relinquish claims to the Norwegian crown and return to Denmark if Sweden would accept the democratic Norwegian constitution and a loose personal union . The Treaty of Kiel was thus tacitly subdued and a new union on more equal terms negotiated . The convention comprised four documents , all written in French , with the following main points : Norwegians were shocked by their government ' s concessions , and when the Swedish general Magnus Björnstjerna , who had led the Swedish negotiations , arrived in Christiania , Norway , he got an unfriendly welcome . Norwegians also directed their resentment toward their own leaders and what they perceived as spineless military defense . Over time , public opinion shifted . The convention was a significant improvement over the terms dictated to Denmark – Norway at the treaty of Kiel . Notably , Norway was no longer to be treated as a Swedish conquest but rather as an equal party in a union of two independent states . Both the principle and substance of the Norwegian Constitution were accepted , and Norway retained its own parliament and separate institutions , except for the common king and foreign service . This was the last war between Sweden and Norway , and Sweden ' s last war .