The term "sergeant" can be given two main definitions; the first being a military rank and the other a governmental role. Whereas technically the two roles were not mutually exclusive, they were very different in roles and duties. The soldier sergeant was a man of what would now be thought of as the 'middle class', fulfilling a junior role to the knight in the medieval hierarchy. Sergeants could fight either as heavy to light cavalry, or as well-trained professional infantry, either spearmen or crossbowmen. Most notable medieval mercenaries fell into the 'sergeant' class, such as Flemish crossbowmen and spearmen, who were seen as reliable quality troops. The sergeant class were deemed to be 'worth half of a knight' in military value. The office originated in medieval England to serve the sovereign in a police role, much like a bailiff in more recent times. Indeed, the sergeants-at-arms constitute the oldest royal bodyguard in England, dating from the time of King Richard I (around 1189) as a formed body. The title "sergeant-at-arms" appears during the crusades during the reign of King Philip II of France in 1192.