In Britain, the Emergency Powers (Defence) Act is passed, giving the government authority over persons and property for the duration of the war. In Paris, Churchill and Reynaud agree to a proposal by new French Commander-in-Chief General Weygand to attack the German salient caused by the Panzer thrust to the coast (essentially the same plan proposed by his predecessor, the disgraced Gamelin). However, it is too little, too late. The Germans are well established and Allied forces in Belgium are too busy fighting a retreat to attack.
Rommel holds near Arras, believing he faced 5 divisions in the British attack yesterday rather than 2 divisions plus 2 tank battalions. Guderian, however, pushes his Panzers North up the coast towards Calais and Boulogne.
Armed British merchant vessel Dunster Grange fights off a surface attack by U-37 using the deck gun, after U-37 misses with 4 torpedoes, off Land’s End. Dunster Grange will arrive safely in Liverpool on May 24. http://www.uboat.net/allies/merchants/ships/321.html