March across the Belts

The March Across the Belts was a campaign between 30 January and 8 February 1658 during the Second Northern War where King Charles X Gustav of Sweden led the Swedish army from Jutland across the ice of the Little Belt to Funen and the Great Belt to reach Zealand. The risky but vastly successful crossing was a crushing blow to Denmark, and led to the Treaty of Roskilde later that year, which handed Scania to Sweden.

During the Second Northern War, King Charles X Gustav of Sweden was bogged down in his war with Poland, unable to reach a decisive conclusion to the hostilities despite taking Warsaw. King Frederick III of Denmark provided a way out of Poland when he declared war on Sweden. The Swedish army could now march from Poland without it looking like a rout. The Swedish army marched to the western and central parts of Denmark from Poland, without returning to Sweden, to avoid fighting its way through then-Danish Scania. Forced marches of several tens of kilometers a day, brought 6,000 Swedish soldiers to Jutland. The Swedish army was not large, but the soldiers were some of the best equipped and best trained troops in Europe. The army swept away the Danish resistance; the remaining Danish did not risk a pitched battle with the Swedes.

On 25 August 1657, the Swedish army stood before the newly completed Danish fortress Fredriksodde on Jutland's east coast. The fortress had a complement of about 8,000 men. This fortress did not exist in 1645 (the last time Charles Gustav had been there). Fredriksodde was besieged by general Karl Gustav Wrangel for two months, and then stormed on the night of 24 October. Few Swedes perished and 6,000 Danes were captured. In addition, the Swedish army now had all of the Jutland army's supplies.

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