Fighting began on Feb 1, 1864 and the Austro-Prussian forces quickly overran Holstein but the offensive slowed in Schleswig which had a mixed population but mostly Danish. The fighting took place in severe winter conditions with frozen rivers and coastal seashore ice. British PM Palmerston wanted to intervene supported by British public opinion but opposed by some in the Cabinet and the Queen. Britain had a naval advantage and 30,000 Royal Marines. Austro-Prussian forces were at least 50,000 and the Danes about 38,000.