The Battle of Arras (also known as the First Battle of Arras, was an attempt by the French Army to outflank the German Army, which was attempting to do the same thing during the "Race to the Sea", the reciprocal attempts by both sides, to exploit conditions created during the First Battle of the Aisne. At the First Battle of Picardy each side had attacked expecting to advance round an open northern flank and found instead that troops had arrived from further south and extended the flank northwards. The Tenth Army, led by General Louis Maud'huy, attacked advancing German forces on 1 October and reached Douai, where the 6th Army under Crown Prince Rupprecht counter-attacked, as three corps of the German 1st, 2nd and 7th armies attacked further south. The French were forced to withdraw towards Arras and Lens was occupied by German forces on 4 October. Attempts to encircle Arras from the north were defeated and both sides used reinforcements to try another flanking move further north at the Battle of La Bassée The reciprocal flanking moves ended in Flanders, when both sides reached the North Sea coast and then attempted breakthrough attacks during the First Battle of Flanders. Background Strategic developments On 28 September, Falkenhayn ordered that all available troops were to be transferred to the 6th Army, for an offensive on the existing northern flank by the IV, Guard and I Bavarian corps near Arras, an offensive by the II Cavalry Corps on the right flank of the 6th Army, across Flanders to the coast and an acceleration of the operations at the Siege of Antwerp, before it could be reinforced. Rupprecht intended to halt the advance of the French on the west side of Arras and conduct an enveloping attack around the north of the city. Prelude Battle of Albert, 25–29 September On 21 September Falkenhayn had decided to concentrate the 6th Army near Amiens, to attack westwards to the coast and then envelop the French northern flank south of the Somme. The offensive by the French Second Army forced Falkenhayn to divert the XXI Corps and I Bavarian Corps as soon as they arrived to extend the front northwards from Chaulnes to Péronne on 24 September and drive the French back over the Somme. On 26 September, the Second Army dug in on a line from Lassigny to Roye and Bray-sur-Somme and German cavalry moved