Western Front
According to several popular accounts, today in 1916, the Royal Flying Corps dropped a wreath over Jasta 2 which read, "To the memory of Captain Boelcke, a brave and chivalrous foe."
Battle of the Somme: Allies capture Dewdrop and Hazy trenches.
Eastern Front
Romania: Romanian counteroffensive in the Transylvanian passes continues, advancing 7 miles and capturing 3000 German and Austro-Hungarian prisoners.
In Dobruja, Romanians still retiring.
Asiatic and Egyptian Theaters
Hussein bin Ali, the Sharif of Mecca, proclaims himself the King of Hejaz and the King of the Arab lands:
http://imgur.com/Kv4ZJx2
Naval and Overseas Operations
U-boat torpedoes Greek volunteer transport
Angeliki.
2 RNAS seaplanes reconnoiter Schillig Roads ( https://www.google.com/maps/place/53%C2%B042'06.1%22N+8%C2%B001'23.9%22E/@53.7017,8.0233,11120m/data=!3m1!1e3!4m5!3m4!1s0x0:0x0!8m2!3d53.7017!4d8. 0233 ) from carrier
Vindex but fail to find boom; no CMB attack carried out.
Jellicoe warns of ‘…serious danger that our losses in merchant ships … may by the early summer of 1917 have such a serious effect … as to force us into accepting peace terms’.
Political, etc.
United Kingdom: Field Marshal Viscount French warns volunteers at Derby that a German invasion of Britain is a possibility, not a mere supposition.