The Vulcan priest who extracts Surak's katra from Archer also performed T'Pol and Koss' wedding ceremony in Home (2004). He was portrayed by Jack Donner, better known for his role as Tal in The Enterprise Incident (1968). Donner's appearance in this episode makes for the longest time period between an actor's first and last appearances in a Star Trek television series (1968 and 2004).
In terms of this episode's chronological (not production) order within the franchise, Talok is the first Romulan character to appear on-screen in Star Trek.
Archer uses the classic Vulcan neck pinch to incapacitate an attacking High Command operative. This is one of the few times in all of Star Trek that a non-Vulcan uses this technique. Albeit in this case, it's his possession of the Vulcan Surak's Katra that grants him this ability.
This is listed as one of the "Ten Essential Episodes" of Star Trek: Enterprise (2001) in the 2008 reference book "Star Trek 101" by Paula M. Block and Terry J. Erdmann.
This is the only episode to feature Shran in which he has no interaction with Captain Archer, either in person or over a viewscreen. Instead he interacts with Commander Tucker, the acting captain while Archer is on the planet below.