First use of gas on the Western Front

Box respirator (gas mask) with its canvas bag. © Hull Museums.


The German army used chlorine gas against the French Algerian division during the First Battle of Ypres. This was the first time that poison gas had been effectively used as a weapon of war.

The Germans had tried to use a form of tear gas against the Russian troops in January 1915 but the attack was a disappointment because the gas was affected by the cold. By April German chemists had invented a means of releasing chlorine gas from pressurised cylinders. Thousands of French Algerian troops, and later British and Canadian troops, were affected during the second battle of Ypres. Gas was also a powerful psychological weapon because it terrified the troops.

Using poison gas was against the rules of warfare as contained in the Hague Convention of 1899. The Allies reacted angrily in public. In private the British government decided that if the Germans were going to use gas, the British could too. The first British gas attack, at Loos in September 1915, failed when the wind blew much of the gas back over the British troops. By 1916 the British had devised a way of using gas in shells rather than canisters which meant it could be fired from a much greater range.

Protecting the troops

British chemists rushed to produce a way of protecting the troops from the effects of gas. The problem was that the enemy kept developing different types of gas, so they had to find a gas mask that would work effectively when a new form was introduced. Their solution was the box respirator. It had a mask that covered the soldier’s face, attached by a rubber tube to a separate canister that contained filters which would protect him from the gas. As different types of gas were developed, all they had to do was issue soldiers with new filters to use with their existing mask. The box respirator was effective as long as the soldier was able to get his mask on in time.

How effective was poison gas?

Soldiers on both sides were terrified by the prospect of a gas attack. However, some historians have argued that it was more effective as a psychological than a military weapon. Throughout the course of the war the British lost 487,994 men on the Western Front. Of this total number of deaths, 5,899 or 1.2% of the total, were attributed to gas. 1% of the pensions awarded for injury caused by war service was to a gas victim.

(source: G. Corrigan, 2004, Mud, Blood and Poppycock. Cassell, London, p. 173.)

See also the BBC News Magazine article ‘How deadly was the poison gas of WW1?’

Learning resources

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