Canadian Forces, 30,000
First Brigade, Gen. Mercer
Second Brigade, Gen. Currie
Third Brigade, Gen. Turner
Artillery, Gen. Burstall
British Cavalry, Gen. Allenby, Gen. Rivington
British Battalions (5), Col. Geddes
French Colonial Division, 20,000
German Force, 150,000
Duke of Wurttemberg's army
From the close of the first battle of Ypres, in November, 1914, until the spring of 1915, the Ypres salient had remained comparatively quiet. About the middle of April, the Duke of Wurttember's army, 150,000 strong, made a partially successful attempt to squeeze out the salient east of Ypres.
In retaliation, the British assaulted the German position on April 17, 1915, capturing Hill 70, an eminence commanding the city on the southeast. Repeated counter attacks by the Germans failed to dislodge them. The general positions of the combatant armies, however, remained practically unchanged, the Germans still holding the Wytschaete and Messines hills.
Early in April, the defenses of the Ypres salient had been somewhat weakened by the transfer south of the best French troops, together with most of the British artillery, to assist in the great spring offensive, which Gen. Foch was about to launch. The breach in the Allied line was filled by three brigades of raw Canadian troops, newly arrived in Belgium, and a division of colored French Colonial troops, mostly Turcos and Zouaves. The watchful Germans thought the conditions most favorable for an attack on the northern face of the salient with a chance of breaking through to the coast.
The First Chlorine Gas Attack
About the middle of April, a deserter from the Gennan lines had warned the Allied commander that the Germans were planning to annihilate the defenders of Ypres with poison gas, but the story was dismissed as a visionary tale.
On the afternoon of April 22, 1915, without further warning, a cloud of greenish-yellow chlorine gas, five miles long, was observed to emit from the German trenches, being...