[1] Berthelot was born in Honfleur, in Normandy, "a handsome, stocky man, blond and fair-skinned, an adventuresome and high-spirited person, with an inquisitive and active mind".

[2] The younger Berthelot's first sea voyage was at the age of twelve, and when he was 19 years old, he embarked on a vessel called L'Espérance, bound for the Far East.

[3] In service with the Portuguese, Berthelot was knighted for bravery and earned an appointment as pilot-in-chief and cosmographer to the king of Portugal.

[4] Though a career with the Portuguese navy was available to him, he chose to join the Discalced Carmelite Order in Goa in 1635, taking the name of Denis of the Nativity.

Castro had requested his presence, both for spiritual guidance for the group as well as for Father Denis' piloting skills and his knowledge of the region from his service aboard the L'Espérance.