It wouldn't be an understatement to say that, of all of the characters across Star Trek's breathtaking canon, Spock is the most seminal. After a year of boldly going across the galaxy, in the episode Journey to Babel, our most important Vulcan comes face to face with his own most important Vulcan. Sorry T'Pring, not you, this is Sarek, Vulcan ambassador, and Spock's father.
Across four separate shows and movies, as well as a showing in the J.J Abrams Kelvin timeline, Sarek has long established himself as a fan favourite. Whether it's his tense interactions with Spock and his crew in TOS, his respectful rapport with TNG's Picard, or his care for Michael Burnham in Discovery, it's fair to say that the Star Trek Universe would be very different without him.
Despite all of this influence, Sarek only has a handful of appearances to his name, yet the few times he does appear onscreen often turn out to be essential episodes. Outside of these fleeting cameos, there is a great deal about this character unexplored in-Universe, and these are just some of those things you may not know.
10. His Appearance Was A Long Time Coming
Before appearing in the second season episode Journey To Babel, Sarek's eventual characterisation and back story would be elaborated on in several conversations aboard the Enterprise in season one.
His first canonical mention, whilst significant, is actually as vague as could one could possibly imagine. Spock simply mentions one of his ancestors who married a human female, with a level of distance later attributed to the fractious relationship between the two.
Further mentions in season one would refer to Sarek in the past tense up until The Squire of Gothos, when Spock confirms that his father lives on Vulcan. This Side of Paradise would subsequently establish Sarek's role as an Ambassador, with episode writer D.C. Fontana later using this as a springboard for the idea of Journey To Babel.
Despite all of this set up, this well regarded yet decidedly vague Vulcan figure still didn't have a name. As is the case with many things Vulcan, the solution to this would be extremely logical. In a memo to Gene Roddenberry, producer Robert Justman proposed that, like Spock, Vulcan names should be no longer than five letters, begin with S and end with K.
Although the naming idea would not stick, it was enough to finally give Spock's much alluded to father a name.