The front of the British 3rd (incomplete), 2nd, and 1st Corps at the opening of the offensive lay, then, from Villiers-sur-Morin, across the edge of the Forest of Crécy, by Mortcerf, Lumigny, Rozoy, and Gastins, to near the Forest of Jouy, where Conneau’s Cavalry Corps connected with the infantry of the 5th Army. The battle here opened with an enemy attack. To mask its withdrawal to the Ourcq, a part of the German II Corps had delivered, early on the morning of September 6, a blow at the British right, and fighting was sharp till noon over the farmlands of the Brie plateau between Hautefeuille and Vaudoy——that is, 8 miles south-west of Coulommiers. “At this time,” says Field-Marshal French, “I did not know that a retreat had really set in, or how the various German corps and divisions were placed.” Columns of the IV Active Corps were still farther south, to the east of Vaudoy, on the Provins road, with large forces of cavalry and the III Corps on their left. It was a delicate part of the front, the space between the British and 5th French Armies. During the afternoon, while the khaki line slowly progressed over the stubble fields and broken forest around the villages of Lumigny, Pezarches, and Touquin, unmistakable evidence began to come in that the German foreguard had become a rearguard, and that the body of the II Corps had been in retreat all day. The charred walls of the hamlets of Courchamps and Courtacon, destroyed with deliberate ferocity, marked the most southerly points of the invasion in the western field.[60] To the Allied soldiers who knew not Maunoury, it must have seemed that their offensive was commencing magically well. About 10 a.m., the British left and centre——the 4th Division and the 2nd Corps——had been surprised to find the pressure on their front suddenly relieved. On their right, the 1st Corps soon saw its way free, and strode northward. At 6.30 p.m., the IV Active Corps received orders to follow the II Corps back to the Ourcq. Thus, by evening on September 6, Sir John French was able to reach the Grand Morin, from Crécy-en-Brie eastward, with scouts beyond the stream at Maisoncelles. Coulommiers, where Kluck had had his headquarters, was occupied during the night.