Battle of Hartmannswillerkopf

A few border skirmishes took place after Germany declared war on France; from 5 August, more German patrols were sent out as French attacks increased. French troops advanced from Gérardmer to the Col de la Schlucht (Schlucht Pass), where the Germans retreated and blew up the tunnel. The French VII Corps ( Louis Bonneau) comprising the 14th Division and 41st Division, advanced from Belfort to Mulhouse and Colmar to the north-east, suffered supply difficulties but 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 defenders had left. In the early morning of 9 August, parts of the XIV Corps and XV Corps of the German 7th Army arrived from Strasbourg and counter-attacked at Cernay; Mulhouse was liberated by German troops on 10 August and Bonneau withdrew towards Belfort. Paul Pau was put in command of a new to re-invade Alsace on 14 August, as part of a larger offensive by the First Army and the Second Army into Lorraine. The began the new offensive against four German brigades, which fought a delaying action as the French advanced from Belfort, two divisions on the right passing through Dannemarie at the head of the valley of the Ill river. On the left flank, two divisions advanced with several battalions, which had moved into the Fecht valley on 12 August. On the evening of 14 August, Thann was captured and the most advanced French troops reached the western outskirts of the city by 16 August. On 18 August, VII Corps attacked Mulhouse and captured Altkirch on the south-eastern flank. By the evening of 19 August, the French had occupied the city, having captured and considerable amounts of equipment. With the capture of the Rhine bridges and valleys leading into the plain, the French had gained control of Upper Alsace but on 26 August the French withdrew from Mulhouse to a more defensible line near Altkirch, to provide reinforcements for the French armies closer to Paris. ==Prelude==

The was dissolved on 26 August and many of its units distributed among the remaining French armies. In September 1914, the German 7th Army was transferred to the Aisne and left three brigades in (Upper Alsace). On 19 September 1914, (An was an improvised force larger than a corps and smaller than an army, subordinate to an army headquarters.) named after its commander Hans Gaede (formerly the chief of staff of the XIV Corps) and renamed (Army Detachment Gaede) on 30 January 1915. ==Battle==

1914–1915 On 25 December, the French 66th Division and a battalion of attacked through deep snow and woods, to improve the French position on the peak of Hartmannswillerkopf. The French attack succeeded but the German defenders were pushed back only a short distance. Division of attacked on a line from Hartmannswillerkopf to the Herrengluh ruins, Wolfskopf and Amselkopf in thick fog from 18 to 21 January 1915 and managed to surround the French positions, recapturing the summit of Hartmannswillerkopf and Hirzstein to the south, a French counter-attack being repulsed. The main German attack on 30 January, near Wattwiller, made early progress then bogged down against the French defences. French attacks against Division from 19 to 27 February were repulsed but on 26 February, a French attack gained . On 5 March, the French captured a blockhouse and a German counter-attack by two regiments was defeated. The 152nd Infantry Regiment arrived to reinforce the ; after a four-hour artillery preparation, the infantry and captured two trench lines and took 250 prisoners but failed to penetrate new German trench lines close to the peak. The French attacked again on 17 and from 23 March – 6 April; on 26 March, after a preparatory bombardment, the 152nd Regiment captured the summit of Hartmannswillerkopf in ten minutes, taking 400 prisoners and finding that the ground had been stripped of trees by the artillery exchanges. The Germans suspended the offensive at Wattwiller and Steinbach to concentrate all reserves in the Hartmannswillerkopf area but on 17 March, the German army chief of staff, General Erich von Falkenhayn, ordered offensive operations in Alsace to cease. The French success had enabled artillery-observers to direct their guns onto the Colmar–Mulhouse railway and local German attacks on 25 April took back the peak; the French recaptured it the next day the 152nd Regiment suffering 825 casualties. 1915–1916 In December 1915, Augustin Dubail commanding (GAE: Eastern Army Group) planned a larger operation to consolidate the French position in the region by capturing Mulhouse. An attack on Hartmannswillerkopf by the 66e Division (General ), which had been fighting in the area all year was to be the prelude to the larger attack. The division was given another 250 guns for the attack, two of which were super-heavy 370 mm Filloux mortars, an average of one gun per of German front. After several postponements, the French bombardment began on 21 December from Hartmannswillerkopf to Wattwiller. In the afternoon the 66e Division attacked, taking the peak and trenches at Hirtzstein to the north-west of Wattwiller as German reserves established a new front line on the eastern slopes. Next day, Brigade 82 of the 12th Division counter-attacked with reinforcements and re-took the peak, except for trenches on the north slope, which fell on 23 December. The French 152e was almost annihilated, suffering 1,998 casualties from 21 to 22 December, along with Serret who was mortally wounded, the Germans taking 1,553 prisoners. On the afternoon of 24 December, Brigade 82 tried to re-gain the lost trenches at Hirtzstein, with the assistance of flame thrower teams but achieved only a partial success. During the evening of 28 December, French attacks captured several positions between Hartmannswillerkopf and Hirzstein, followed by German counter-attacks during the night; from 29 to 30 December and on 1 January 1916. The original front line was restored and on 8 January, Brigade 187 re-captured the trenches at Hirzstein that had been lost on 21 December. ==Aftermath==

Casualties The fighting from 20 December 1915 to 8 January 1916 cost the French 7,465 casualties, about 50 per cent of the attacking force, of whom 1,103 were taken prisoner, along with thirty machine-guns. The Germans suffered 4,513 casualties, 1,700 men being taken prisoner. Dubail stopped offensive operations to rest the survivors and to avoid French resources being drained away to little purpose; in (4 January 1916) Dubail recommended that such enterprises be avoided. ==Gallery==

File:Map of the Sundgau 1914-1918.png|Sundgau, front line, 1914–1918 File:French attack, Hartmannswillerkopf, 22 Mar 15.png| French attack, 22 March 1915 File:French attack at Hartmannswillerkopf, 26 Mar 15.png| French attack, 26 March 1915 File:German attack, Hartmanswillerkopf, 25 Apr 15.png| German attack, 25 April 1915 File:French attack, Hartmannswillerkopf 21 Dec 15.png| French attack, 21 December 1915 File:German counter-attack, Hartmannswillerkopf, 22 Dec 15.png| German counter-attack, 22 December 1915 File:French and German positions at Vieil-Armand during the stalemate, 1916-1918.png| French and German positions at Vieil-Armand, 1916–1918 ==Notes==