British Expeditionary Force

British Expeditionary Force (BEF), the UK's contribution to the Anglo-French alliance which took part in the fighting which preceded the fall of France in June 1940. It initially comprised some 152,000 men formed into two corps of two infantry divisions each, plus their supporting arms, though ultimately it was hoped to field two armies of two corps each. Commanded by Gort, it began its move to France on 4 September 1939 and was placed in the line on the Belgian border between the French First and Seventh Armies. The 1st Corps, commanded by Lt-General Dill, then by Lt-General M. Barker, comprised 1st and 2nd Divisions and the 2nd Corps, under Brooke, 3rd and 4th Divisions, and there was also an air component of 9,392 RAF personnel and 12 squadrons of aircraft.

Though mechanized, or rather motorized, the BEF was a purely defensive force. It had no armoured division, few tanks, inadequate communications, equipment, and training, and insufficient air power for any kind of offensive operation even if the French Army, under whose command it came, had been in any frame of mind to initiate one. It was, as the commander of its 3rd Division, Montgomery, remarked, ‘totally unfit to fight a first class war on the Continent of Europe’. Instead, it prepared defensive positions, did some much-needed training, and waited to see what would happen (see phoney war).

In December 1939 the BEF was reinforced by the newly formed 5th Division (withdrawn in April 1940) and the following April the 51st (Highland) Division was sent to the Maginot Line on the Saar Front. Eight territorial divisions were also added between January and April 1940, though half of these had little equipment and less training and were really nothing more than labour battalions (nevertheless, they fought with great tenacity when they found themselves in the path of the German Army Group A). By May the BEF's strength totalled 394,165 men, though more than 150,000 of these were in the rear areas and were mostly without military training.

When the German offensive started on 10 May the BEF advanced to the Dyle Line in Belgium, but it was soon forced to withdraw and six days later began its evacuation from Dunkirk. But this still left 140,000 British troops in France. Some, including the remnant of the 1st Armoured Division—which had lost two-thirds of its strength after arriving in France on 21 May—escaped across the River Seine; 2,137 were evacuated from Veules-les-Roses and more than 10,000 from Le Havre; but the 51st (Highland) Division was forced to surrender at St-Valéry-en-Caux on 12 June. The next day Brooke, having replaced Gort, arrived at Cherbourg to command a reconstituted BEF reinforced by the 1st Canadian Division and the 52nd (Highland) Division. But the new French C-in-C, Weygand, had already advised the French government to seek an armistice and Brooke, with difficulty, persuaded Churchill that a Brittany redoubt was impossible and that all troops must be withdrawn immediately. Some 136,000 men and 310 guns, plus 20,000 Polish troops, were safely evacuated though more than 3,000 perished when the 20,000-ton liner Lancastria was bombed at St Nazaire.

Thanks to Dunkirk and other evacuations the BEF's casualties—68,111 killed, wounded, and captured, plus 599 deaths through non-battle causes—were not as disastrous as they would otherwise have been. But its matériel losses, which included nearly 64,000 vehicles and 2,472 guns, were little short of catastrophic, while RAF losses amounted to 931 aircraft and 1,526 casualties.