Though Norway was part of the union with Denmark during the Thirty Years' War, it was largely spared direct involvement in the conflict, which primarily took place in Central Europe. Denmark-Norway, under King Christian IV, entered the war in 1625 to support Protestant interests against the Catholic Habsburgs. However, Norway's role was more supportive, providing resources and manpower rather than being directly involved in battles.
Norwegian troops were conscripted to fight in Christian IV's campaigns, and the war put a heavy economic strain on Norway, with increased taxes and the burden of supplying soldiers and materials. The Danish-Norwegian involvement ended in 1629 after Christian IV’s defeat, but the economic consequences persisted. The war's impact on Norway was mainly indirect, with the country serving as a resource base for Denmark’s efforts in the conflict.