The Battle of Boulogne was the defence of the port of Boulogne-sur-Mer by French, British and Belgian troops, during the Battle of France in 1940. The battle was fought at the same time as the Siege of Calais, just before Operation Dynamo, the evacuation of the British Expeditionary Force (BEF) through Dunkirk. After the Franco-British counter-attack at the Battle of Arras (21 May) German units were held ready to resist a resumption of the attack on 22 May, despite the protests of General Heinz Guderian, the commander of XIX Corps, who wanted to rush north up the Channel coast to capture Boulogne, Calais and Dunkirk. An attack by part of the XIX Corps was not authorised until 12:40 p.m. on 22 May, by when the Allied troops at Boulogne had been reinforced from England by most of the 20th Gu