Contributor(s): Dr Heather Jones | The prisoner reprisals of 1917 were a retaliatory action taken by German forces against captured French and British troops, in reaction to poor British and French treatment of German prisoner workers. This was a ruthless, calculated policy, intended to manipulate public opinion, as Heather Jones from the Department of International History explains. Prisoners held behind German lines during the 1917 reprisals were forced to work under shellfire on subsistence rations. But rather than conceal this mistreatment, the German captors actively encouraged prisoners to write home about it . This deliberate release of information was intended to mobilise public opinion in Britain and France in order to force changes in British and French military policy. The plan worked. As a direct consequence of the 1917 reprisal sequences, the French and British governments insisted, against the wishes of their military chiefs, that their German prisoner workers be withdrawn to safety. In consequence, the Germans halted their reprisals in May of 1917. However, the reprisals ultimately paved the way for more radicalised German prisoner mistreatment later in the war. By 1918, beatings and malnutrition were commonplace in the German army, and actions which a year before had been sufficiently shocking as to constitute a "reprisal" had become the norm. A book on this topic will be published with Cambridge University Press in 2011: Heather Jones, Violence against prisoners of war: Britain, France and Germany, 1914-1920 (Cambridge: Cambridge University Press, 2011)