As early as the 14th century, when the old Confederation contended with foreign armies, both the people and their rulers recognised that strict rules of war and efficient military criminal procedures were essential if discipline in the field was to be maintained. The oldest federal rules of war date back to the Sempacher Charter of 1393.

Later, it was no longer general discipline but rather one's own rules that took priority. As a result, in the 17th century, a special criminal code applied to mercenaries, i.e. troops serving in foreign armies. They were not subject to the punitive power of their military commanders but instead to that of their own leaders, i.e. not to a foreign system, but to the justice handed down by their own judges under their own system of laws. Accordingly, Art. VIII of the Charter of 1663 governing the military alliance of the Confederates with Ludwig XIV states '...and justice shall be administered by the judges of the Nation and by no others.' With impressive obstinacy, the Tagsatzung, the parliament of the early 19th century, held fast to these principles whenever foreign courts or commanders tried to assert their criminal jurisdiction over Swiss mercenary troops.

A further principle of the 19th century was no 'foreign judges'. In addition to federal troops, there were at first also cantonal troops, who were subject to the jurisdiction of their own cantonal courts martial. In the course of the centralisation of the armed forces in the Federal Constitution of 1874, the Federal Act of 28 June 1889 on the Organisation of the Military Tribunal System was finally enacted after the rejection of several earlier drafts. This represented a unification of all the cantonal military regulations in one federal military statute.

During the First World War, it became clear that the criminal law did not comply with modern requirements. The legal precedent up to that time had been sparse and inconsistent. In response to this need, the Military Criminal Code (MStG) of 13 June 1927 was enacted, and it remains valid to this day - subject of course to numerous amendments - complementing the civilian Criminal Code of 1937. In addition, the military tribunal system has since 1979 followed a modern Federal Military Criminal Procedure Code. It is thus ensured - and rightly so - that members of the armed forces will continue to be judged by their own specialised courts.