Western Front
Kaiserschlacht: Hostile “counter-attack” (once again, probably just a raid, not a full counter-attack) north-west of Merville fails.
Successful British raids on Lys front and Arras district.
Mannheim, etc., heavily bombed by British airmen: 7 Handley Page bombers (1 lost) of No 216 Squadron RAF cause two-day plant closure at Oppau chemical works, Mannheim (direct hit on gas main). Rail workshops and locomotives hit at Karthaus. 13 F.E.2s of No 100 Squadron dislocate rail traffic at Saarbrücken (night May 21-22).
A Handley Page O/400 bomber:
https://i2.wp.com/ww2-weapons.com/w...e-400.jpg?ssl=1
Raid on Paris by two Gothas, one downed.
Rumpler C-VII (Drechsel and Foell) flies daring 375-mile high-altitude undetected photo-reconnaissance sortie over London, returns safely to Tournai base.
Ernst Udet appointed Commander Jasta 4.
Eastern Front
Increasing unrest at Kiev; acts of terrorism ineffectually repressed by Germans.
Southern Front
2 SVA-5s of Italian 87th Squadriglia photograph Zeppelin works at Friedrichshafen (440-mile round trip).
Naval and Overseas Operations
French sailors manning a gun on a French Navy ship:
https://twitter.com/CenturyAgoToday...236928708358144
Mozambique: General Edwards' troops come up with German-aligned forces’ rearguard nine miles south-west of Nanungu.
Asiatic and Egyptian Theaters
Armenia: Turkish 36th and 9th Divisions throw back Nazarbekov’s c.9,000 Armenians from Amamll Station until May 22; Antranik’s 2,000 Armenians make rearguard stand near Jelal-oglu from May 22-23.
Political, etc
Russia: SOVNARKOM starts peace talks with Hetman Skoropadski (of the Ukraine) on May 23.