Under the law of 14 October 1791, all active citizens and their children over 18 years were obliged to enlist in the National Guard. Their role was the maintenance of law and order and, if necessary, the defence of the territory. Following a nationwide scheme decided on in September 1791, the National Guard was organised on the basis of district or canton companies. Five of these neighbourhood units (designated as fusiliers or grenadiers) made up a battalion. Eight to ten battalions comprised a "legion". Districts might also provide companies of veterans and young citizens, respectively drawn from volunteers of over 60 or under 18. Where possible, there was provision for mounted detachments and artillerymen.