Henries was born around 1829 PD. He began his career in the Royal Manticoran Merchant Marine, but rose through the ranks, eventually earning a Naval commission and a knighthood through hard service. By 1906 PD, he held the rank of Admiral and was in command of a battle squadron. While en route to the Thetis System, he stopped by in the Yeltsin's Star System in order to conduct five training excerizes with Admiral Honor Harrington's Battle Squadron One and High Admiral Wesley Matthews's Battle Squadron Two. The first was won by the Graysons, the second and third resulted in draws. During the fourth exercise, he and his staff used a stealthed reconnaissance drone to spy on Harrington's formation, and were able to win due to better intelligence.