Family legend was that he was a soldier of the Carignan regiment. In an email from Dave Toupin. President, Filles Du Roi Org. he says
"In Peter Gagne's bio note on Catherine Ducharme (in his book , King's Daughters and Founding Mothers, Vol. I, p226) he notes that Pierre Roy is listed in the 1666 census as a servant of Jacques Le Ber of Montreal.