World War I casualties
Casualty statistics for World War I vary to a great extent; estimates of total deaths range from 9 million to over 15 million. Military casualties reported in official sources list deaths due to all causes, including an estimated 7 to 8 million combat related deaths (killed or died of wounds) and another two to three million military deaths caused by accidents, disease and deaths while prisoners of war. Official government reports listing casualty statistics were published by the United States and Great Britain. These secondary sources published during the 1920s, are the source of the statistics in reference works listing casualties in World War I. This article summarizes the casualty statistics published in the official government reports of the United States and Great Britain as well as France, Italy, Belgium, Germany, Austria and Russia. More recently the research of the Commonwealth War Graves Commission (CWGC) has revised the military casualty statistics of the UK and its allies; they include in their listing of military war dead personnel outside of combat theaters and civilians recruited from Africa, the Middle East and China who provided logistical and service support in combat theaters. The casualties of these support personnel recruited outside of Europe were previously not included with British war dead, however the casualties of the Labour Corps recruited from the British Isles were included in the rolls of British war dead published in 1921. The methodology used by each nation to record and classify casualties was not uniform, a general caveat regarding casualty figures is that they cannot be considered comparable in all cases.
Horses in World War I
The continued resupply of horses was a major issue of the war. One estimate puts the number of horses that served in World War I at around six million, with a large percentage of them dying due to war-related causes. In 1914, the year the war began, the British Army owned only about 25,000 horses. This shortfall required the US to help with remount efforts, even before it had formally entered the war. Between 1914 and 1918, the US sent almost one million horses overseas, and another 182,000 were taken overseas with American troops. This deployment seriously depleted the country's equine population. Only 200 returned to the US, and 60,000 were killed outright. By the middle of 1917, Britain had procured 591,000 horses and 213,000 mules, as well as almost 60,000 camels and oxen. Britain's Remount Department spent £67.5 million on purchasing, training and delivering horses and mules to the front. The British Remount Department became a major multinational business and a leading player in the international horse trade, through supplying horses to not only the British Army but also to Canada, Belgium, Australia, New Zealand, Portugal, and even a few to the US. Shipping horses between the US and Europe was both costly and dangerous; American Expeditionary Force officials calculated that almost seven times as much room was needed per ton for animals than for average wartime cargo, and over 6,500 horses and mules were drowned or killed by shell fire on Allied ships attacked by the Germans. In turn, New Zealand lost around 3 percent of the nearly 10,000 horses shipped to the front during the war.