Western Front
Second Battle of the Marne (German: Unternehmen Friedensturm): High-water mark of the War. End of Unternehmen Friedensturm. Great Allied counter attack on 27-mile front between Fontenoy (6.5 miles north-west of Soissons) and Belleau (6 miles north-west of Chateau-Thierry). Franco-Americans, backed by 2000 guns, attack at 0435 hours. French Tenth Army (Mangin) including US 1st and 2nd Divisions (among 9) supported by 223 tanks (62 hit), achieves complete surprise, and advances up to 4 1/2 miles. French reach Monte de Paris (1 mile from Soissons) and 5 miles of Crise Valley, east of Buzancy. South of Ourcq, French and Americans secure line Marizy-Hautvesnes-Belleau. South of Marne Germans reach St. Agneau. East of Reims French retake Prunay and defeat Prussian Guard east of Prosnes. Allies take 12,000 PoWs and 250 guns from 11 German divisions.
Flanders: Ludendorff holds morning Mons conference (with Rupprecht, army commanders and staffs for projected ‘final offensive’ Hagen scheduled early August), thrown into confusion by news of Marne debacle. Ludendorff immediately sends 2 divisions to threatened front, but news of fresh defeats abruptly ends conference. Army Group Crown Prince William orders 14 German divisions south of the Marne to retire, Ludendorff cancels planned thrusts around Reims and halts transfer of Bruchmueller’s artillery to Flanders. At 1535 hours Rupprecht is ordered to dispatch 2 more divisions to Reims, his diary comments ‘no doubt that we have passed the zenith of our successes’. Ludendorff rows with Hindenburg twice as latter insists on counter-attack from north of Soissons.
French 1st Air Division gives close support to Allied ground attack (for heavy losses) at Chateau-Thierry and Soissons. Comprises 590 aircraft in 2 Groupements each with 12 escadrilles Spad S.13 fighters; 1st Groupement has 9 escadrilles Breguet 14 day bomber and reconnaissance aircraft; 2nd Groupement 6 Breguet escadrilles. RAF (aircraft attached to French XI Corps) also gives support. Allies lose 34 aircraft (14 to JG1) to 8 German. Sergeant Willi Gabriel of Jasta 11 scores 4 victories. Germans regain air supremacy over parts of Marne battlefield (July 22, when 41 Allied aircraft lost for 2 German; until August 6).
French Schneider tanks: https://twitter.com/CenturyAgoToday...495765939548161
French Chasseurs cyclists resting near the forest of Villers-Cotterêts during the French counteroffensive: © IWM (Q 78084): https://twitter.com/CenturyAgoToday...556172171530240
Airplane raid on Kent; no casualties.
British soldiers picking cherries near Robecq, France: © IWM (Q 11080): https://twitter.com/CenturyAgoToday...223985102442497
RAF officer training to fire a gun in a moving “cockpit”: © IWM (Q 10370): https://twitter.com/CenturyAgoToday...254190042906627
Ruined church of Saint-Venant, France: © IWM (Q 70565): https://twitter.com/CenturyAgoToday...586381071503361
British pilot holding a stuffed owl toy at the aerodrome near St. Omer: https://twitter.com/CenturyAgoToday...616588260171778

Eastern Front
Following the assassination of Tsar Nicholas II and his family, Soviet Cheka agents execute several relatives of the Romanov family in Alapayevsk. Grand Duke Sergei Mikhailovich is shot, while the rest are thrown down a mining shaft and grenades are dropped in.

Political, etc
Austria-Hungary: Debate in Reichsrat re: "German Course" of Austrian policy.
United Kingdom: Sir L. Worthington-Evans succeeds Lord Robert Cecil as British Minister for Blockade (see February 23rd, 1916).
Japan: Japanese Diplomatic Council approves U.S.'s proposal for intervention in Siberia.
South Africa: (Nelson) Rolihlahla Mandela is born in the village of Mvezo, South Africa.

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