In the Protocol Additional to the Geneva Conventions (GC) of 12 August 1949, and relating to the Protection of Victims of International Armed Conflicts (Protocol I), 8 June 1977 it is stated:

Art 47. Mercenaries

A mercenary is any person who:
1-is specially recruited locally or abroad in order to fight in an armed conflict;
2-does, in fact, take a direct part in the hostilities;
3-is motivated to take part in the hostilities essentially by the desire for private gain and, in fact, is promised, by or on behalf of a Party to the conflict, material compensation substantially in excess of that promised or paid to combatants of similar ranks and functions in the armed forces of that Party;
4-is neither a national of a Party to the conflict nor a resident of territory controlled by a Party to the conflict;
5-is not a member of the armed forces of a Party to the conflict; and
6-has not been sent by a State which is not a Party to the conflict on official duty as a member of its armed forces.

There have been mercenaries since the time of Egypt through Medieval times all the way into the present.

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