Throughout history, animals have played an important role in armed conflict. Horses, elephants, dogs and various other members of the animal kingdom used from the pre-Christian era right up to modern times.

Equines, of course, were the mainstay of many armies, not only in cavalry units, whose charges have been long celebrated, but also as pack mules for transportation of weapons and other supplies required on the battlefield.

War elephants were deployed in India and North Africa, their large size and powerful strength instilling fear in enemy troops. During the Second Punic War, Hannibal famously took his troops with their horses and war elephants up through France, crossed the Alps, and descended on the Romans in the Italian peninsula, creating havoc with his powerful pachyderms.

The utilisation of non-human forces in warfare continued right up to the present century.

On the eve of the anniversary of the Armistice, which brought the First World War I to an end, it is fitting to record the various roles played by animals in this global conflict which was without parallel – its scale of destruction eclipsing all previous wars.

Estimates of the casualties and deaths on both sides are staggering: nearly 10 million military and over seven million civilian deaths, together with about 21 million wounded in action.

Before the outbreak of the war in 1914, battles had been fought mainly by opposing cavalries, soldiers on horseback wielding swords and guns.

This type of conflict in World War I was restricted to the desert campaigns in North Africa where horse and camel cavalry regiments fought out many battles between the British and Arab rebels and the Germans and their Turkish allies. Horses and camels were also used here for transportation of weapons, ammunition and food supplies and for transportation of wounded soldiers.

In the European theatre of war, however, such cavalry-based warfare became impractical when the system of trench warfare and the use of modern automatic weaponry were introduced. Both the British and German military authorities realised that mounted soldiers could not win the war in the trenches.

The last major cavalry charge of World War I took place at Moreuil Wood in March 1918 with very high casualties on both sides. A quarter of the men and half the soldiers were killed. One horse which survived was the legendary Warrior, mounted by General Jack Seely. Seely and Warrior had served throughout the entire war, travelling to France in 1914 and returning home in the winter of 1918.

General Seely mounted on Warrior, the equine hero of World War I (from a 1918 painting by Sir Alfred Munnings).

Warrior was dubbed “the horse the Germans could not kill” and was the inspiration behind the book War Horse by Michael Morpurgo, which was produced as a successful film by Steven Spielberg.

Equines, however, still played an important part on the Western Front, though not as fighting cavalry horses. Because of the deep mud and bomb craters at the front, horses, donkeys and mules were the only practical means of carrying food, water, ammunition and medical supplies to men at the battlefront.

The last message, successfully delivered [by a pigeon] in spite of suffering shots in an eye and a leg, was instrumental in saving 194 US soldiers

Dogs also made a valid contribution to the war effort on both sides. They were considered to be the hardest workers, serving in a variety of roles. Germany employed about 30,000 dogs while the British and their allies used about 50,000.

Guards were often accompanied by specially trained dogs, especially Dobermans, which were taught to give warning barks or growls when they sensed enemy activity in the vicinity. Smaller dogs, especially terriers, were used as rat catchers in the trenches, which were always heavily infested with these rodents. Casualty dogs, also termed mercy dogs, made an important contribution: they were trained to find wounded men on the battlefield and were equipped with medical supplies to assist the suffering.

A soldier and his horse wearing gas masks.

Dogs were also used as messengers, a job for which they proved to be very reliable. Trench warfare meant that communication was always problematical; human runners offered potentially large targets, and weighed down by uniforms there was a chance that they would not get through with important messages. Dogs provided the obvious solution to this pressing problem.

Other jobs entrusted to dogs included laying telephone wires across muddy ground, transporting carrier pigeons to the front, and as mascots to raise the morale of the troops.

One of the most famous dogs of World War I was Stubby, a Staffordshire terrier who was adopted by Private Conroy of the 102nd Infantry, 26th Yankee Division. He became the regimental mascot and accompanied the troops to France where his exploits became legendary.

Stubby was capable of detecting enemy gas well before the men and he would bark and run around to sound the alarm, saving many lives. He also served as a mercy dog, and once caught a German spy mapping the Allied trenches, holding him until he could be captured; for this action he was promoted to sergeant! Stubby served in 17 battles and received many awards and medals for his outstanding service.

The spectacular ‘Animals in War’ Memorial at Park Lane, London.

A messenger dog with a spool attached to a harness for laying out a new telephone line.

Pigeons have been used since time immemorial as messengers, exploiting their unerring ability to return to what they consider their home. During World War I, both sides made regular use of pigeons to carry messages, in a canister attached to a leg, from the frontline trenches back to base headquarters.

When they landed in their home loft, tripwires would sound a buzzer which alerted the Signals Corps who would go to the loft, take the message out of the canister and send it on to its final destination. Pigeons were in constant danger during flight as enemy troops would attempt to shoot them down.

One pigeon deployed by American forces, nicknamed Cher Ami, delivered 12 important messages during the Battle of Verdun. The last message, successfully delivered in spite of suffering shots in an eye and a leg, was instrumental in saving 194 US soldiers who had been isolated. For her exploits, Cher Ami was decorated, receiving the French Croix de Guerre with palm.

It has been estimated that a total of around 100,000 pigeons were deployed during the war.

Another important role carried out by animals was their use as mascots to raise the morale of the fighting troops. Some of these became quite famous. The terrier Stubby mentioned previously was one of these famous military mascots.

Sergeant Stubby, the most decorated dog of World War I.

Another was a pig named Tirpitz which first served as a mascot on the German cruiser SMS Dresden. When the Dresden was sunk, Tirpitz was rescued by the crew of the British ship HMS Glasgow and remained its mascot until 1916.

Equally famous was the mascot of Canadian troops in England, a black bear named Winnipeg. In 1914, when the Canadians left for action in France, Winnipeg was presented to London Zoo. A.A. Milne took his son Christopher Robin to the zoo to see Winnipeg and was inspired to write the stories of Winnie the Pooh.

Perhaps the most unusual animals that were used during World War I had the role of detecting deadly mustard gas before the troops, thus affording time to the troops to wear their gas masks. Caged birds were used for this purpose, but the US Army came up with a novel mustard gas detector – the slug!

Dr Paul Bartsch was in charge of the Mollusc Section of the National Museum of Natural History and he discovered that slugs could detect the presence of mustard gas in very small concentrations. They reacted by closing their breathing pores and their bodies would shrink.

Soldiers in the trenches tasked with observing the slugs would notice this and warn the other men to put on their gas masks. These lowly molluscs, then, were responsible for saving many lives.

It has been estimated that over 16 million animals were used during World War I, including horses, camels, dogs, pigeons and others. In 1943, an award – the Dickin medal – was established by the People’s Dispensary for Sick Animals (PDSA) to honour the work of animals in World War II.

The bronze medallion was presented posthumously to an animal hero of World War I, General Seely’s horse Warrior. It is inscribed “For Gallantry – Honouring All Animals that Served in WWI 1914-1918”.

Monuments have also been erected to honour animals who served in war, including the spectacular memorial ‘Animals in War’ in London’s Park Lane, inaugurated by Princess Anne in November 2004.

Tirpitz, the pig which served as a mascot for both sides during the war.

One of the many carrier pigeons of World War I.