In 1940, Hitler turned west. In April, his forces occupied Denmark and Norway to protect Germany’s northern approaches. In May, they overran the Netherlands, Belgium, and Luxemburg. Germany’s defeat of France in May and June was a terrible shock. Most expected a long stalemate as in World War I. Mussolini’s Italy, which hoped to acquire numerous Mediterranean territories, joined Hitler’s war on June 10, attacking France and later Egypt and Greece. Britain, under Winston Churchill after April 1940, fought alone, enduring German air attacks and the threat of invasion.