Collapse of France

During the winter of 1939-40 the French army and the German Wehrmacht faced one another in what was regarded satirically as the sitzkrieg, or sit-down war. The world waited in anticipation of a major conflict between two powerful forces. On May 13, 1940, a bridgehead was established at Sedan, considered the gateway to France, and then suddenly, on May 16, a day after the Dutch capitulation, the German blitzkrieg was released on northern France. German mechanized forces outflanked the Maginot Line, surprised the Allies by attacking through the wooded Ardennes rather than the Belgian plain, and drove the British Expeditionary Force (BEF) from the Continent at Dunkirk ( Dunkerque). On June 5 the Germans launched another offensive southward from the Somme. They entered Paris unopposed on June 14 and forced France to sign an armistice at Compiègne on June 22, 1940.

The fall of France was an extraordinary victory for Hitler. The supposedly unbeatable French army had melted away before the onslaught of his mobile units, with their convincing display of mechanized power. Nazi Germany then occupied most of France and permitted the establishment of a friendly government at Vichy, in central France on the Allier River.

The Vichy Government was headed by Marshal Henri Pétain, hero of World War I, and Pierre Laval, a collaborationist. Disgruntled French patriots rallied around Gen. Charles de Gaulle, who pronounced himself leader of the Free French.

During the early months of the war Benito Mussolini maintained Italy's neutrality. When France was about to fall he decided to join the Nazis. Declaring war on the Allies on June 10, 1940, he invaded southern France in what U.S. president Franklin D. Roosevelt described as a "stab-in-the-back."

Dunkirk Retreat

During the Belgian campaign the Germans drove rapidly across southeastern Belgium and turned toward Abbeville on the French coast, thereby isolating Allied troops. The BEF and its French comrades appeared to be doomed. While some of the troops of the French First Army sold their lives in a fierce rearguard action, from British ports sailed one of the strangest armadas in history composed of destroyers, motor launches, private yachts, old ferries, steamers, even fishing smacks, about 850 vessels in all. While planes of the Royal Air Force (RAF) provided an umbrella over the scene to drive off German bombers, the fleet of British vessels moved to Dunkirk and proceeded to evacuate about 338,000 British, French, and Belgian troops from May 26 to June 4, 1940. Not only was a military disaster turned into a propaganda victory, but several hundred thousand experienced troops were saved for future action against the Axis.

Battle of Britain

Hitler, anticipating further eastern conquests, hoped that Britain would accept German control of the Continent and seek peace. But Britain shunned the chancellor's overtures of July 1940, and, in August, Hermann Goering's Luftwaffe began an all-out attack on British ports, airfields, and industrial centers and, finally, on London. The goal was to crush British morale and wipe out the RAF in preparation for Operation Sea Lion, an invasion of England.

The Battle of Britain was the first great air battle in history. For 57 nights London was attacked by an average force of 160 bombers. The outnumbered RAF, employing the effective Spitfire fighter and aided by radar, destroyed 1,733 aircraft while losing 915 fighters. German air power could not continue sustaining such heavy losses, and in October, Operation Sea Lion was postponed indefinitely.