|The following is based on Fallout Tactics and some details might contradict canon.|
Nathan was one of Brotherhood of Steel scribes who traveled East in one of the airships that pursued the super mutant army, in the same zeppelin as Paladin Latham. After the airship crashed near Osceolla the few survivors were captured by super mutants and scheduled for execution by mutant leader Gammorin. They were saved by their leader, Latham, who killed Gammorin in a single unarmed combat and therefore became a new leader of a super mutant army. Ironically, the one who once saved Nathan's life became his murderer. Losing his sanity due to a head injury during the combat with Gammorin, Latham cut Nathan's throat with a ripper, believing to be attacked by a deathclaw.