Champagne and Marne – SECOND BATTLE OF THE MARNE: ALLIED COUNTERSTROKE. Franco-Americans, backed by 2000 guns, attack at 0435 hours on 27-mile front, Fonteroy-Belleau. French Tenth Army (Mangin) including US 1st and 2nd Divisions (among 9) supported by 223 tanks (62 hit), achieve complete surprise advances up to 4 1/2 miles to within a mile of ‘Mt Paris’, Soissons and Crive Valley. Allies take 12,000 PoWs and 250 guns from 11 German divisions. Farther south, Franco-Americans (Degoutte) advance 3-5 miles north of Marne. Germans reach St Agnan south of Marne.
Flanders: Ludendorff 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.
Western Front: 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 S13 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 af Marne battlefield (July 22, when 41 Allied aircraft lost for 2 German; until August 6).