John D.

John D. was a member of the Railroad in 2266.

Background
In November of 2066, he was the sole survivor of a raid on the Railroad's HQ; Wyatt cites him as a major force in the group's subsequent reorganization. His recruitment methods proved to be the basis of the Railroad's "pyramid" structure of information distribution, and he is credited with the development of their dead drop system.

His ultimate fate is unknown, as records left by Pinky Thompson make no mention of his fate following the 2273 Institute ambush that killed Wyatt. In 2284, Desdemona privately speculated that "John D." was a pseudonym of the enigmatic Railroad agent Deacon, though no evidence exists to confirm or deny this.

Appearances
John D. is mentioned only in Fallout 4.