The man known only as the Lieutenant was the lieutenant of the Black Company. In his youth he sailed as a cabin boy, where he learned ships. Later he received an education in military engineering, specifically siege weapons. By the time he joined the Black Company he was already an experienced soldier and tactician.
When the Captain died following the Battle of Juniper the Lieutenant was distraught. Elected captain of the Black Company he never warmed to the title, still preferring to be called the Lieutenant, even though he led the mercenary band for over 15 years. During his years of leadership the Company was the backbone of the White Rose Rebellion and he reported to Darling, the White Rose reborn.
The Lieutenant was a staunch traditionalist when it came to matters of the Black Company and did not often fraternize with the other members. When he did socialize it was over a game of tonk. He was a poor tonk player, even worse than One-Eye. According to Croaker he had a bizarre sense of humor though he seldom showed it.