Eugene Mallory was a Starfleet officer who served in the mid-23rd century. He had one son, a Lieutenant Mallory, who also was a member Starfleet. (TOS novel: Academy: Collision Course)

In 2250, Eugene Mallory supported James T. Kirk's entrance into Starfleet Academy, along with Captain Robert April and Admiral La Forge. (TOS novels: Best Destiny and The Galactic Whirlpool)

In 2267, his son was killed on a landing party mission to Gamma Trianguli VI, while he was under Kirk's command. (TOS episode: "The Apple")