The war was prompted by Swedish involvement in the Franco-Dutch War. Sweden had allied with France against several European countries. The United Provinces, under attack by France, sought support from Denmark–Norway. After some hesitation, King Christian V started the invasion of Skåneland (Scania, Halland, Blekinge, and sometimes also Bornholm) in 1675, while the Swedish were occupied with a war against Brandenburg. The invasion of Scania was combined with a simultaneous Norwegian front called the Gyldenløve War, forcing the defending Swedes to fight a two-front war in addition to their entanglements in the Holy Roman Empire.