War crimes trials

A war crimes trial is the trial of persons charged with criminal violation of the laws and customs of war and related principles of international law committed during armed conflict.

The trial of Peter von Hagenbach by an ad hoc tribunal of the Holy Roman Empire in 1474, was the first “international” war crimes trials and also of command responsibility. Hagenbach was put on trial for atrocities committed during the occupation of Breisach, found guilty, and beheaded. Since he was convicted for crimes, "he as a knight was deemed to have a duty to prevent", although Hagenbach defended himself by arguing that he was only following orders from the Duke of Burgundy, Charles the Bold, to whom the Holy Roman Empire had given Breisach.

In 1865, Henry Wirz, a Confederate officer, was held accountable and hanged for appalling conditions at Andersonville Prison where many Union soldiers died during the American Civil War. After World War I, a small number of German personnel were tried by a German court in the Leipzig War Crimes Trials for crimes allegedly committed during that war.

Article 227 of the Treaty of Versailles, the peace treaty between Germany and the Allied Powers after the First World War, “publicly arraign[ed] William II of Hohenzollern, formerly German Emperor, for a supreme offence against international morality and the sanctity of treaties.” The former Kaiser had escaped to the Netherlands, however, and despite demands for his extradition having been made, the Dutch refused to surrender him, and he was not brought to trial. Germany, as a signatory to the treaty, thus was placed on notice as to what might occur in the event of a subsequent war.

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