In the Second Battle of Flanders – also known as the Second Battle of Ypres – in World War I, German troops attempted to penetrate Allied positions on the Western Front in Flanders in a renewed offensive on April 22, 1915, to eliminate the frontal arc at Ypres. The German army used chemical weapons in the form of chlorine gas for the first time in this offensive. The breakthrough failed due to a lack of reserves, but the front arc was reduced in size. The engagement is counted among the four battles of Flanders.
After the failure of the German breakthrough attempts in the First Battle of Flanders in November 1914, strong units – among others the Guards Corps, the XIII Army Corps and the III Reserve Corps – had been transferred to the Eastern Front at the turn of the year. On March 14 and 15, parts of the II Bavarian Army Corps had succeeded in bringing the high position of St. Eloi into German hands; they had thus come closer to the necessary strategic goal – the conquest of the Kemmelberg. Although no reserves were available, General Erich von Falkenhayn, the head of the German Army Command, ordered a limited attack in the Ypres area in the 4th Army section to test the effect of a newly developed war gas. The army commander in charge of the attack, Albrecht von Württemberg, was assigned the Gheluvelt – Langemarck – Yser Canal section as the attack section. The Chief of Staff of the 4th Army, Major General Ilse, organized the course of the gas operation with Colonel Peterson, the chemical weapons leader. Whether the conquest of the Channel ports was Falkenhayn”s strategic objective remains questionable; in any case, the reserves provided speak against this assumption. Only five divisions (45th, 46th, 51st, 52nd, and 53rd Reserve Divisions) were scheduled for the initial attack.
Since Christmas 1914, the defense of the Ypres Arc had been the responsibility of the newly formed British 2nd Army. Its commander, General Horace Smith-Dorrien, was in charge of the III Corps under General William Pulteney on the right wing, the II Corps under General Charles Fergusson in the center and the V Corps under General Herbert Plumer in the eastern apron around Ypres, only the latter subsequently came into the main German attack field. To the north of Ypres, the French army division Détachement d”armée de Belgique of General Gabriel Henri Putz defended with the allied Belgians about the front on the Yser Canal between Bixschoote and Langemark, where east of it the link-up with the fresh Canadian division took place.
Between Steenstrate and Poelkapelle, the German engineer regiment 35 released 150 tons of chlorine gas from 6000 steel cylinders within five minutes at 6 p.m. on April 22, 1915. A white-yellow poisonous cloud stretched for 6 km in width against the French positions. Since chlorine gas is heavier than air, it sank into the Allied trenches and positions. The remnants of the opposite French Corps de Mitry with the 87th as well as the 45th (the soldiers had no gas protection (e.g. gas masks). The German XXIII Reserve Corps under General von Kathen then succeeded in taking the Allied position on the Yser Canal without enemy resistance and advanced three to four kilometers deep. The Germans, however, had no gas masks themselves, which was to inhibit further advance.The 51st Reserve Division succeeded in capturing Langemarck, and the eastern Yser bridgehead at Het Sas was wrested from the French by the German 46th Reserve Division. In addition, the Germans also succeeded in capturing the heights of Pilkem.
On April 23, Steenstrate, defended by the French 153rd Division brought forward from the reserves, and the village of Lizerne fell into the hands of the XXIII Reserve Corps. At Gravenstafel, the British 50th Division, brought up from the reserve, immediately began relieving counterattacks. On April 24, the German XXVI Reserve Corps under General von Hügel with the 51st and 52nd Reserve Divisions also vigorously intervened in the battle and engaged the 1st Canadian Division under General Edwin Alderson in heavy fighting northwest of Ypres near St. Julien. The battle surged back and forth between Broodseinde and Langemarck without decision. Because the German side had failed to provide sufficient reserves, the gap in the front that had opened up north of Ypres could not be exploited. All subsequent German attacks were repulsed.On April 26, the French side led by General Foch also began counterattacks against the German right wing. On April 27, the Germans had to evacuate the village of Lizerne on the west bank of the Yser Canal again and were thrown back on the canal front from Drie Grachten to Het Sas.On the east bank between Bixschoote and Pilkem, the front solidified. The Germans confined themselves in late April to shelling the exposed 1st Canadian and 27th and 28th British Divisions west of Ypres with artillery from three sides. To avoid this, these three divisions were withdrawn to a shorter defensive line in front of Ypres from 1 to 4 May. The German XXVII Reserve Corps under Richard von Schubert in the Gheluvelt area and the XV Army Corps under Berthold von Deimling at Hollebeke now also participated in the attacks.
General Smith-Dorrien already wanted to go back and voluntarily reduce the front arc of Ypres. British Commander-in-Chief John French then relieved him of his command and installed General Herbert Plumer in his place as the new leader of the 2nd Army. The command of Plumer”s V Corps and thus the defense of the front arc was given to General Edmund Allenby, the former leader of the cavalry corps in reserve at Ypres.From May 2 to 9, 1915, the Germans again tried to force a breakthrough with renewed use of poison gas. Attacks against the Canadians at the Battle of Frezenberg yielded little in the way of terrain gains and were brought to a complete halt after the British 4th Division intervened. The second phase of the German offensive had thus also failed. On May 24, the Germans attacked once again without success at the Battle of Bellewarde. On May 25, 1915, the German Supreme Army Command had to abandon the breakthrough attempt due to excessive losses, and the Second Battle of Ypres had to be called off. General Falkenhayn had no reserves ready for a continuation, because after the successful Battle of Gorlice-Tarnów all available troops were given priority to the Eastern Front. In Flanders, fighting continued until mid-June, with the focus on Hooge and Lombartzyde.
John Condon, 14, considered the youngest casualty of Allied troops in World War I, died in a May 24 chlorine gas attack at Ypres Arch.