Image of King Charles X Gustav of Sweden

King Charles X Gustav of Sweden.(8 November 1622 – 13 February 1660).

Dano-Swedish War

This War was fought from 1658 to 1660. It was an offshoot of a previous conflict as Denmark had delayed in keeping to some of the agreements as set out when peace was declared. The idea behind this war all began when the Swedish king Charles X Gustav wanted to gain the Province of Prussia (located in Poland) to be under Swedish control. Yet Sweden did not have enough power in the region to carry out this plan or sufficient international support. The Poles were also keen to attack Sweden.

Instead Sweden declared war on Denmark and since Denmark had procrastinated in fulfilling the provisions of their peace agreement, the Swedes stated that as their just cause. The Swedish king may have thought Denmark an easier target at the time, as it was during their recent conflict that Sweden had been victorious.

The intention was to destroy Denmark as a sovereign power and to tear down the main city of Copenhagen. Doing this would then enable Sweden to have free reign to declare war on Europe, without being interfered with by the Danes.

The Swedes set sail for Denmark with a fleet of 5700 men in 70 ships. At first the Swedish Army surrounded the city of Copenhagen in a quest to starve the inhabitants. As the Danes expected the Swedish invasion, they had burnt houses outside the city wall and closed the city gates. These gates would remain closed for almost two years (22 months). During these months Sweden bombarded the city with howitzers (short guns firing shells at high elevation) and other weapons. The Danes fought back with their artillery from within the city walls.

Yet the Dutch came to the Danes rescue with a fleet of reinforcement and fought off the surrounding Swedes. The Dutch did this to honour their obligation to a 1649 treaty whereby the Dutch promised to defend Denmark against unprovoked aggression. Then the Swedes laid an assault on the city, which also failed. Then Brandenburg, Poland and Austria joined the war in opposition to Sweden.

In the second month of 1660, the Swedish king died of pneumonia and without his presence the main blockage to peace was gone. Soon a treaty was signed, the treaty of Olivia between Sweden, Austria, Brandenburg and Poland. The Danes however were not too keen to give into peace and convinced the Dutch to support them furthermore. There was a serious possibility of war being started between the Swedes and Dutch. At this point the English and French supported Sweden by intervening, to try prevent an outbreak of another war.

It was however a Danish statesman that organised a treaty of peace with Sweden that did not need any other direct foreign input or intervention. This treaty was organised within weeks. This was the treaty of Copenhagen and it resulted in peace and the return of Bornholm to Denmark and Trøndelag to Norway. This treaty also declared and established borders between Sweden, Denmark and Norway.

These borders established from this treaty are of historical importance and still exist to current times.

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