initiatives, later named the Battle of the Frontiers. The German deployment plan, II, included the massing of German forces (less 20 per cent to defend Prussia and the German coast) on the German–Belgian border. The force was used to execute an offensive into Belgium, to force a decisive battle on the French army on territory further north than the fortified Franco-German border. The French began to implement Plan XVII with a deployment for an offensive into Alsace-Lorraine and Belgium. French strategy required the Russians to be brought into action as quickly as possible: 'to do so Joffre had promised to launch his own attack at the earliest opportunity [and] had no choice but to attack across the common frontier in Alsace and Lorraine'. The French attack into Alsace-Lorraine was defeated because of inadequate tactics, a lack of artillery-infantry co-operation and by the fighting capacity of the German armies, which inflicted huge numbers of casualties. French formations moved forward with insufficient reconnaissance. The attacks in southern Belgium were conducted with negligible reconnaissance or artillery support and were repulsed without preventing the western manoeuvre of the German armies in the north. While the attacks in the Ardennes starting on 22 August achieved strategic surprise in heavy fog, the French columns advancing were themselves unprepared and surprised by German presence in the area and were unable to attack due to a breakdown in command and control. Within a few days the French were back in their starting positions, having suffered a costly defeat. The Germans advanced through Belgium and northern France against the Belgian, British and French armies and reached an area to the north-east of Paris but failed to trap the Allied armies and force a decisive battle on them. The German advance outran its supplies and slowed; Joffre was able to use French railways to move the retreating armies and re-group behind the river Marne and within the Paris fortified zone, faster than the Germans could pursue. The French defeated the faltering German advance with a counter-offensive at the First Battle of the Marne, assisted by the British. Helmuth von Moltke the Younger, Chief of the German General Staff, had tried to apply the offensive strategy of I (a plan for an isolated Franco-German war, with all German forces deployed against France), to the inadequate western deployment of II (only 80 per cent of the army assembled in the west), to