May I draw your attention to the amazing life story of James Kirker - an Irishman who became one of the most notorious Indian hunters of the old west and who at one stage was known as the King of New Mexico. Indeed he sounds like a despicable character - however, this account from 1847 upon a rare visit by him to St.Louis, casts him in a slightly different light:

"he is still the free, kind hearted aquaintance, yet years of peril, privitation and exposure have done their work in altering his outward man: while his long association with the Mexicans and Indians has so changed his accent that few would suspect him of being a son of the Emerald Isle. Col. Kirker is a highly intelligent man, and the experience he has aquired by his intercourse with the semi-barbarians of the West, has pre-eminently qualified him to aid the public service at this crises..."