First Khitomer Accords
The explosion of the Klingon moon Praxis in 2293 caused severe ecological disasters on the Klingon Homeworld and an almost complete shutdown of Klingon economy. Following these events, the Klingon chancellor Gorkon initiated peace talks with the Federation in which Captain Spock served as special envoy to the Empire. The peace conference was first scheduled to be held on Earth, but was later relocated due to Chancellor Gorkon's assassination on his way to Earth. The new venue was Camp Khitomer, on the Klingon planet Khitomer, which was kept secret in order to prevent further assaults. Despite further actions by a Klingon/Federation/Romulan conspiracy, the Khitomer Conference was a success and a turning point in Klingon-Federation relations. (Star Trek VI: The Undiscovered Country)
Curzon Dax represented the Federation in the negotiations, at which the Romulan Senator Pardek was also present. (DS9: "You Are Cordially Invited"; TNG: "Unification I")
As part of the agreement, the Empire relinquished its historical claims to the Archanis sector, which is located in Federation territory on the Klingon border. (DS9: "Broken Link")
In 2344, the Battle of Narendra III had a decisive influence on interstellar history. Having been betrayed by the Romulan Star Empire, and witnessing the courage of the Enterprise-C, this event had the effect of finally ending Romulan-Klingon relations and solidifying Federation-Klingon relations. (TNG: "Yesterday's Enterprise")
Second Khitomer Accords
The Second Khitomer Accords banned the use of Subspace weapons. The Son'a openly flouted this accord in 2375. (Star Trek: Insurrection)
- It was never established in the film whether the Son'a were parties to the Second Khitomer Accords and therefore bound by the ban.
It is possible that the second accords may be the 'peace treaty' referred to by Richard Castillo in "Yesterday's Enterprise", suggesting a signing date in the 2340s. The second accord could be the formal alliance between the Federation and the empire referenced in The Next Generation. It is also possible that it occurred after the events DS9: "By Inferno's Light" in which the Federation and the Klingon Empire renewed their alliance. This is supported by the fact that Chancellor Gowron and Admiral Ross said in DS9: "When It Rains..." they had met at Khitomer.