Multiple realities
(covers information from several alternate timelines)

Gene Roddenberry (also known as G. Roddenberry) was a Starfleet officer in the 23rd and 24th centuries. He was a flag officer with the rank of admiral in 2363.

In 2293, he was listed as a Starfleet Command officer on the dedication plaque of the USS Enterprise-B. (Star Trek Generations, dedication plaque)

In 2353, he was listed as a Starfleet Operational Support Services officer on a directory placard for Starbase 32, Maxia sector. His office was located in room #15850. (TNG: "Violations", directory)

In 2357, William T. Riker was awarded the degree of Master of Science from Starfleet Academy. Roddenberry's signature was on the graduation diploma. (TNG: "Conundrum")

In the 2360s and 2370s, he held the title of Chief of Staff, Starfleet Command, San Francisco. He was listed on the dedication plaques of several Federation starships. (TNG: "Encounter at Farpoint", "Silicon Avatar" dedication plaques; TNG: "The Wounded", dedication plaque; TNG: "Redemption II", dedication plaque; DS9: "Second Sight" dedication plaque; DS9: "The Die is Cast", dedication plaque; VOY: "Caretaker", dedication plaque; Star Trek: First Contact, dedication plaque; VOY: "Message in a Bottle", dedication plaque; DS9: "Valiant", dedication plaque; DS9: "The Dogs of War", dedication plaque)

On stardate 47302.5, Harry Kim was awarded the Cochrane Medal of Excellence from the Zefram Cochrane Institute for Advanced Theoretical Physics. Roddenberry's signature was on the award. (VOY: "Non Sequitur", set artwork [1])

In the anti-time future, he was listed as a Starfleet Command officer on the dedication plaque of the USS Pasteur. (TNG: "All Good Things...", dedication plaque)

This character was only mentioned in writing.
He was named after Star Trek creator and showrunner Gene Roddenberry.
Community content is available under CC-BY-NC unless otherwise noted.