Commander of the American Expeditionary Force, Lieutenant General John J Pershing, lands at Boulogne, 13 June 1917. Image courtesy Imperial War Museum © IWM (Q 5510).
- Day 1050 of the war
- London suffers its highest civilian casualties of the war as 18 German Gotha bombers raid the city, killing 157 and injuring 432
- Commander of the American Expeditionary Force, Lieutenant General John Joseph “Black Jack” Pershing, arrives at Boulogne, France, where he receives a tumultuous welcome. Footage of General Pershing’s arrival in France
- Forty-three people are killed at Ashton-under-Lyne when five tons of TNT explodes at the Hooley Hill Rubber and Chemical Company munitions factory. The explosion ignites two nearby gasometers, sending a massive fireball hundreds of metres into the air. Several hundred people are injured. Tragedy on the Home Front: Munitions Explosion in Ashton
- Allied forces on the Southern Front occupy Trikala and Volo
- German submarine SM U-69 torpedoes the merchant cruiser HMS Avenger in the Atlantic Ocean west of the Shetland Islands. One person is killed.
