Jørgen Bjelke was a Norwegian officer and nobleman. He was born at Elingaard Manor on Onsøy near Fredrikstad, in Østfold County, Norway and died in Kalundborg, Denmark.
He served as a captain in the Hannibal Feud 1644-45. He subsequently saw Danish imperial service in the fighting against the Swedish forces in Germany. During what is referred to in Norway as "the Bjelke Feud", lieutenant general Bjelke served as the commander-in-chief of the Norwegian army. In August 1658 Charles X of Sweden ignored the recently negotiated Treaty of Roskilde and invested Copenhagen. The Norwegian army mobilized under the leadership of Jørgen Bjelke. Belke's goal was to recapture Trøndelag in the north and to defend the southern Norwegian border at Halden, an areas which Charles X had demanded be turned over to Sweden as it provided both an excellent port for timber export from the newly acquired Bohuslän and a point from which further invasions of Norway could be launched. In September 1658 the new Swedish governor of Bohuslän invaded Norway with 1,500 men and attempted to invest Halden. The inhabitants put up a vigorous defense and the Swedes retreated to Bohuslän. Gjerset indicates that, "Peder Vibe was commandant of Trondhjem, but the expedition against Sweden in this quarter was to be led by Jørgen Bjelke, probably the ablest officer in the Norwegian army at that moment. His forces numbered 2000 men, who had been recruited primarily in Trøndelagen. With this force he invaded Jaemtland and Herjedalen, drove out the Swedish garrisons, and returned the two provinces once more under Norwegian administration." Five months later, in February 1659, the Swedes again attacked. Since the first attack, Bjelke had directed the garrison to be strengthened. Under the leadership of Tønne Huitfeldt, the Norwegians again repulsed the Swedish forces. Concurrently, Huitfeldt began construction of fortifications. Cretzenstein, later to be renamed Fredriksten, was the citadel of the fortification system. After each attack on Frederiksten, Bjelke invaded the former Norwegian province of Bohuslän and twice succeeded in reconquering most of it.
