Admiral Caius Fesidas was a Starfleet officer in the late 23rd century. His son was Julius Fesidas - who by 2294 was also a Starfleet Admiral. Fesidas worked at Starfleet Headquarters and was a friend of James T. Kirk.
Fesidas was a frequent patron of the Flag and Grog, a popular bar near Starfleet Headquarters. Fesidas would often become so drunk that a junior officer would accompany him to the Flag and Grog to ensure that he got home okay without causing embarrassment to himself or Starfleet.
In 2294, Fesidas ensured that Kirk would have access to Starfleet computer resources in his quest to free Captain Hikaru Sulu and several of his shipmates from a band of Beta Promethean pirates. (TOS novel: The Fearful Summons)