Britain: Trenchard accepts command of Independent Air Force for bombing Germany.
Salonika: 6 RAF aircraft drop 4,500lb bombs (in 72 sorties) on Bulgar Drama airfield, 24 aircraft bomb rail stations and dumps on May 13-14; 27 aircraft bomb Hudova airfield (repeated on May 21, 23, 29, 30); probable 8 Bulgar aircraft shot down in May.
Southern Russia: Germans occupy Rostov-on-Don.
USSR: Red Army forms General Staff under Lenin’s friend Major-General Bonch-Bruevich with 5 fronts.
Mediterranean: Royal Navy convoy sloop Wallflower depth charges and sinks veteran U-32 attacking convoy 40 miles northwest of Malta.
Adriatic: 4 Austrian destroyers fail to land raiding party to cut coast railway north of Pescara (night May 8-9).
Nicaragua: Government declares war on Germany and Austria.