In France during the Middle Ages, there were two Great Officers of the Crown 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 12th century. Another organisation, the Constabulary (French: Connétablie), was under the command of the Constable of France. The constabulary was regularised as a military body in 1337. Under King Francis I (who reigned 1515–1547), the Maréchaussée was merged with the Constabulary. The resulting force was also known as the Maréchaussée, or, formally, the Constabulary and Marshalcy of France.