Horses and mules were heavily employed by the military during World War I. Over 200,000 animals were obtained at the start of the war from the UK, Spain, Portugal, India, South Africa and New Zealand. The horses were placed into squadrons then deployed to the troops on the frontline.

Horses were used to carry weaponry including ammunition and guns as well as troops and often carried a combined weight of over 280 lbs on their backs. With many horses dying or becoming injured the army had to buy about 15,000 more per month to maintain numbers.

War horses and mules were extremely underfed and received less than a quarter of the food an equivalent animal in the UK would have. It is reported that starving horses were seen trying to eat the wheels of carts.

It is believed that in WWI at least 8 million horse, mules and donkeys died on all sides.