Prisoners of war in World War I

Between 7–9 million soldiers surrendered and were held in prisoner-of-war camps during World War I. All nations pledged to follow the Hague Conventions on fair treatment of prisoners of war, and the survival rate for POWs was generally, though not always, much higher than that of combatants at the front.

The conditions of the POW camps were, in general, satisfactory (and much better than in World War II), thanks in part to the efforts of the International Red Cross and inspections by neutral nations. However, conditions were terrible in Russia and the Ottoman Empire. Starvation was common for prisoners and civilians alike. About 15–20% of the prisoners in Russia died, and as did 8% of Russians imprisoned by the Central Powers. In Germany, food was scarce, but only 5% died. Soldiers that surrendered were not always taken as POWs, as they were sometimes gunned down by the prevailing army instead.

25–31% of Russian losses (as a proportion of those captured, wounded, or killed) were to prisoner status, for Austria-Hungary 32%, for Italy 26%, for France 12%, for Germany 9%; for Britain 7%. Prisoners from the Allied armies totalled about 1.4 million (not including Russia, which lost 2.5–3.5 million soldiers as prisoners). From the Central Powers about 3.3 million soldiers became prisoners; most of them surrendered to Russians.

While the Allied prisoners of the Central Powers were quickly sent home at the end of active hostilities, the same treatment was not granted to Central Power prisoners of the Allies, many of whom served as forced labour, e.g., in France until 1920. They were released only after many approaches by the Red Cross to the Supreme War Council. German prisoners were still being held in Russia as late as 1924.

Living conditions
The conditions at the camps were variable. While those put to work in agriculture fared well, other forms of work were dangerous to POWs, such as the digging of the Rouvre tunnel near the Étang de Berre in France, the demining of battlefields in France in 1919, comparable to those of the Russian gulag on the construction site of the railway line from Petrograd to Murmansk. This extreme situation was, however, not motivated by a punitive desire, but rather by the inorganization and negligence of the authorities. Article 7 of the Hague Convention provides for "treatment of prisoners in terms of food, clothing and bedding equivalent to that of the troops of the government which captured them". In fact, the prisoners' rations were conditioned by the supplies of each country. The prisoners of the Central Powers affected by the Allied blockade (Germany and Austria-Hungary) suffered from hunger like the rest of the population. The French prisoners benefited from packages from their families which alleviated the deficiencies. From July 1916, the French government sends weekly collective packages of 2 kg of bread per prisoner. Russian prisoners deprived of this assistance particularly suffered. In France and the United Kingdom, countries little affected by shortages, prisoners' rations remained more satisfactory. The prisoners were struck by epidemics, typhus and cholera, especially at the start of the war, a period of unpreparedness for the unexpected influx into Russia and Germany. Subsequently, sanitary conditions improved.

The number of prisoners who died during the war would be 751,000 (8.7% of the total), including 478,000 Austro-Hungarian prisoners, 122,000 Germans, 38,963 French in Germany. 411,000 prisoners died in Russia (the majority of them Austro-Hungarian), and more than 100,000 Italian prisoners out of 350,000 in Austria-Hungary.

The overall mortality rate would be around 17.6% among captives in Russia, 7% in Austria, 5.3% in France, 3.5% in Germany. 122,000 German prisoners died among the 933,000 held by the Allies during the war, an average rate of 12.4%, varying from 1.92% in the United States, 3.03% in the United Kingdom, 9.4% in France, 37% in Russia and 39% in Romania. These differences are mainly due to differences in material conditions but also in the average duration of captivity, short in the United States, longer in France where the last prisoners were released at the beginning of 1920, in Russia where repatriations hampered by the civil war were continued until 1922. The high mortality rate in Russia is mainly due to climatic conditions, the unpreparedness of the authorities in the face of an unforeseen influx (lack of accommodation at the start of the war), not to a desire for persecution, that of Italian prisoners due to malnutrition in Austria affected by an extreme food shortage due to the refusal of the Italian government to send relief.

POWs in the Ottoman Empire
The Ottoman Empire often treated POWs poorly. Some 11,800 British Empire soldiers, most of them Indians, became prisoners after the siege of Kut in Mesopotamia in April 1916; 4,250 died in captivity. Although many were in a poor condition when captured, Ottoman officers forced them to march 1100 km to Anatolia. A survivor said: "We were driven along like beasts; to drop out was to die."

Return of the prisoners
The November 1918 armistice provided for the repatriation of Allied prisoners without reciprocity. This lack of reciprocity is a violation of Article 20 of the Hague Convention of 1899, which reads: "After the conclusion of peace, the repatriation of prisoners of war shall be carried out as quickly as possible". The English prisoners were repatriated in November, and the return of the French prisoners ended in mid-January 1919. German prisoners were held in France until the beginning of 1920. The release of Austro-Hungarian and German prisoners in Russia, as well as Russian prisoners in Austria-Hungary and Germany, was provided for by the Treaty of Brest-Litovsk. This return was quite slow (500,000 Austro-Hungarians out of 2,000,000) and the Russian Civil War delayed the repatriation of some of the prisoners from Russia until 1922. The October Revolution and the Civil War also delayed the return of Russian prisoners from Germany.