The three-part Vulcan saga in Star Trek: Enterprise season 4 explained why the 22nd century era Vulcans feared humans. The Enterprise season 4 episodes "The Forge," "Awakening," and "Kir'Shara," introduced the younger version of Star Trek: The Original Series icon T'Pau (Kara Zediker). With the help of Captain Jonathan Archer (Scott Bakula) and T'Pol (Jolene Blalock), T'Pau was able to restore the teachings of Surak and expose a conspiracy between the Vulcan High Command and the Romulan Star Empire.
In Star Trek's timeline, Enterprise picks up less than a century after the events of Star Trek: First Contact, when Dr. Zephram Cochrane (James Cromwell) achieved Mankind's first successful warp flight, which brought the curious Vulcans to Earth. In Enterprise's mid-22nd century, however, relations between humans and Vulcans were far from idyllic. United Earth's Starfleet, and Captain Archer in particular, were hostile toward Vulcans, who they felt were restricting human ambition to explore the galaxy. In turn, the Vulcans were arrogant and condescending to humans. Enterprise's Vulcans behaved differently from how Star Trek fans expected, and there was an undercurrent of racism present from both cultures. This is something T'Pol, Archer, and the NX-01 Enterprise crew overcame over their years serving together.
