The Gendarmerie is heir to the Maréchaussée (Marshalcy—see below), the oldest police force in France, dating back to the Middle Ages. It has influenced the culture and traditions of gendarmerie forces all around the world—and especially in the former French colonial empire.
The Gendarmerie is the direct descendant of the Marshalcy of the ancien regime, more commonly known by its French title, the Maréchaussée.
During the Middle Ages, there were two Grand Officers of the Kingdom of France with police responsibilities: The Marshal of France and the Constable of France. The military policing responsibilities of the Marshal of France were delegated to the Marshal's provost, whose force was known as the Marshalcy because its authority ultimately derived from the Marshal. The marshalcy dates back to the Hundred Years War, and some historians trace it back to the early twelfth century.
In 1415 the Maréchaussée fought in the Battle of Agincourt and their commander, the "Prévôt des Maréchaux" (Provost of the Marshals), Gallois de Fougières, was killed in battle. His existence was rediscovered in 1934. Gallois de Fougières was then officially recorded as the first known gendarme to have died in the line of duty and his remains are now buried under the monument to the gendarmerie in Versailles.