Air War
Western Front: Immelmann and Boelcke share a victory, latter’s third.
Eastern Front
German Tenth Army (Eichhorn) takes Vilna and 22,000 PoWs.
Sea War
Holtzendorff withdraws all UÂ-boats from Southwest Approaches and Channel due to US diplomatic protests. Pohl recalls High Seas Fleet U-boats as he refuses to operate under Prize Regulations: U-boat campaign virtually confined to Mediterranean.
Western Front
Flanders: French guns and Royal Navy shell German-held Belgian coast.
Southern Front
Italian Front: Slight Italian successes along whole front.