August, Joffre directed the Third, Fourth and Fifth armies, together with the Belgians and British, to attack the German armies around Thionville and Luxembourg, where corps were thought to have assembled. The Third and Fourth armies were to defeat German forces between Thionville and Bastogne, as they attacked westwards towards Montmédy and Sedan. The Fifth Army was to intercept German forces advancing towards Givet and then the Fourth Army was to swing north and attack the southern flank of the German armies. The Third and Fourth armies would defeat decisively the main German armies in the west and for this, two more corps were added to the four in the Fourth Army, taken from the flanking armies. Alsace Battle of Mulhouse, 7–10 August The first French offensive of the war, known as the Battle of Mulhouse, began on 7 August. Joffre had directed the First and Second armies to engage as many German divisions as possible to assist French forces operating further north. The French VII Corps with the 14th and 41st divisions, under the command of General Bonneau, advanced from Belfort to Mulhouse and Colmar to the north-east. The French quickly seized the border town of Altkirch south of Mulhouse with a bayonet charge. On 8 August, Bonneau cautiously continued the advance and occupied Mulhouse, shortly after its German garrison had left the town. The First Army commander General Auguste Dubail preferred to dig in and complete the army mobilisation but Joffre ordered the advance to continue. With the arrival of two corps of the German 7th Army from Strasbourg, the Germans mounted a counter-attack on the morning of 9 August, at nearby Cernay. Mulhouse was recaptured on 10 August and Bonneau withdrew towards Belfort to escape a German encirclement. General Paul Pau was put in command of a new Army of Alsace and Bonneau, the VII Corps commander, was (dismissed) by Joffre. VII Corps was reinforced with the 44th Division, the 55th Reserve Division, the 8th Cavalry Division and the 1st Group of Reserve Divisions (58th, 63rd and 66th Reserve divisions) to re-invade Alsace on 14 August, as part of the bigger offensive by the First and Second armies into Lorraine, which drew most of the German 7th Army northwards. The Army of Alsace began a new offensive against four Landwehr brigades, the VII Corps advancing from Belfort with two divisions on the right passing through Dannemarie, at