These men are/were not mercenaries!
“A mercenary is a person who takes part in an armed conflict, who is not a national or a party to the conflict, and 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”
The definitions seem to point to BW being mercenaries.