April 13 (Fri.)
Bolivia breaks off diplomatic relations with Germany.
On the fifty-mile front between Loos and west of Cambrai the British take a number of important villages, including Vimy and Givenchy-en-Gohelle; south of the Scarpe they capture a portion of the Hindenburg line. The French attack and gain ground south of St. Quentin.
April 14 (Sat.)
The British capture Liévin (the western suburb of Lens), Cité St. Pierre (north-west of Lens), and Gricourt (near St. Quentin).
An Allied air-raid on Freiburg, as a reprisal for the sinking of hospital ships.
April 15 (Sun.)
German counter-attacks are repulsed by the British.
The British transports Cameronia (140 lives lost) and Arcadian (279 lives lost) are sunk by submarine in the Mediterranean.
April 16 (Mon.)