The Battle of Trangen took place on 25 April 1808 at Trangen in Flisa, Hedemarkens Amt, between Swedish and Norwegian troops, as a part of the Dano-Swedish War of 1808-1809. The invading Swedish troops, led by Colonel Carl Pontus Gahn, were surrounded and forced to surrender by the Norwegian troops under the command of Bernhard Ditlef von Staffeldt. Gahn and around 450 of his troops were captured. Background After the Swedish setback at Skabukilen on 13 April, they were victorious at Lier on 18 April, when they drove the Norwegians back to Kongsvinger Fortress. General Gustaf Mauritz Armfelt, now headquartered at Lier, hoped to take the strategically important fortress through a pincer movement with the help of Gahn's "Flying Corps". The plan was that Gahn should advance with his troops across the border from Midtskog and on to Åsnes, and from there march south along the river Glomma to Kongsvinger. The Swedish advance On the evening of 24 April Gahn crossed the Swedish-Norwegian border with the 2nd battalion of the Dalarna Regiment, and moved westwards, along the southern side of Flisa River. He chose to march at night to surprise the Norwegian outposts. At dawn, the battalion was near the Flisa River, where it faced the first Norwegian outposts, who immediately fired warning shots and sent out a report about the Swedish advance. The Norwegian defenders The defending troops, commanded by Colonel Bernhard Ditlef von Staffeldt, had begun establishing a defense in the area in early April 1808. Staffeldt's brigade consisted of a grenadier battalion of the 2nd Trondheim Infantry Regiment (2. Throndhjemske Infanteriregiments grenaderbataljon) commanded by Major Johan Georg Ræder, the Southern Norwegian Ski Battalion (Den søndenfjeldske Skiløberbataljon) commanded by Major Frederik Wilhelm Stabell, the Lærdal Light Infantry Company (Lærdalske lette infanterikompani) commanded by Captain Wilhelm Jürgensen, and some troops from Oppland Dragon Regiment (Oplandske Dragonregiment). Staffeldt, unsure the Swedish plans, hesitated to give the order to attack. He found it highly unusual that the Swedes marched into Trangen, a narrow pass between the cliffs of Kjelsås and Buttenås, without sending troops forward along the main road on the north side of the river, and therefore feared that it was a trap. He nevertheless sent 270 men under the command of Captain Elias Nægler to the defensive position at Trangen, which had been prepared with roadblocks of trees, and where it was likely that the Swedish troops would pass.