Overview
Tuvok was born in 2264 on Vulcanis, a lunar colony belonging to the Vulcan people. As a teenager Tuvok fell in love with Jara, the daughter of a Terrelian diplomat. Jara did not return his affections. He was expelled from school. His parents sent him to study then with a Vulcan master to learn to control his emotions.
Tuvok attended Starfleet Academy in San Francisco. Upon graduation, he was commissioned an Ensign at age 29, serving as Junior Science Officer on the USS Excelsior, under Captain Hikaru Sulu (seen in the episode "Flashback") .
During his early service with Starfleet, Tuvok became increasingly uncomfortable associating with non-Vulcans, and he resigned his Starfleet commission in 2298 to pursue his people's Kolinahr regimen of true non-emotion. He went into pon farr six years later, leading to his marriage to T'Pel, and began a family.
50 years later, after much self-examination, Tuvok rejoined Starfleet as a training instructor at Starfleet Academy. His return to Starfleet was marked by a maturity and a reconsideration of the benefits service provided. After a few years teaching cadets, Tuvok was briefly assigned to the USS Billings under Commander Kathryn Janeway, until both Janeway and Tuvok were assigned to the USS Wyoming and then the Intrepid-class starship USS Voyager, as Captain (Janeway) and Security & Tactical Officer (Tuvok).
In 2371, Tuvok was assigned to infiltrate the Maquis organization aboard Chakotay's Maquis vessel. During the mission, Tuvok's identity was uncovered by a Maquis intelligence agent, who uses Tuvok as a laboratory specimen for mind-control experiments. While Tuvok was conscious throughout the experiments, the agent wiped his memory when he had finished, ensuring that Tuvok was unable to remember any details. Following the ordeal, Tuvok was released back amongst the Maquis. During an incident involving the Maquis ship and the USS Voyager, both vessels were unwillingly transported to the Delta Quadrant by the enigmatic Caretaker. When the Maquis ship was destroyed by crashing into a Kazon ship to save the USS Voyager, Tuvok was transported off the ship with a handful of other survivors, and resumed his duties as Security & Tactical Officer.
At that time, Voyager also picked up two Delta Quadrant natives, Neelix, a Talaxian, and his partner Kes, from Ocampa. Tuvok recognized Kes' psionic abilities and helped her develop them. Tuvok learned to tolerate Neelix's overly friendly and emotional behavior. Later, a transporter accident fused Tuvok and Neelix together into a new humanoid appropriately named "Tuvix". They were eventually restored to their individual forms under the orders of Captain Janeway, using a procedure devised by the EMH and chief engineer B'Elanna Torres. Tuvok still had issues with Neelix after the experience and many of them are raised again in the episode "Riddles". The two eventually became friends, though it was more apparent from Neelix's end.
At the opening of the 4th season episode "Revulsion", relatively dated 2374, Tuvok was promoted to the rank of Lieutenant Commander. Before this in most of the 1st season he is frequently referred to as "Lieutenant", even though he wears Lieutenant Commander rank insignia.
It is learned during the final episode of the series that Tuvok suffers from a degenerative neurological disease, which can only be cured by undergoing a mind-meld with a family member. In 2377, he was still well enough to perform his duties. However, in his elderly years, in an alternate timeline, the disease finally ravaged Tuvok's mind as he was not able to return to the Alpha Quadrant in time for a cure. This left him confined to a mental hospital. However, in order to save Tuvok among others, Captain Janeway's future-self changed history, by finding a way to return the Voyager crew to the Alpha Quadrant back in 2378, the time before his disease worsened.
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