Chancellor Gorkon was head of the Klingon High Council in Star Trek VI: The Undiscovered Country which was a point of great crisis for the Klingon Empire. The moon Praxis exploded due to unsafe mining practices, causing great environmental damage to the Klingon capital world Qo'noS, depleting its ozone layer. According to official reports, the planet would soon be completely uninhabitable.
Because of the catastrophe, Gorkon sought help from the Federation and initiated peace talks. The USS Enterprise was dispatched to rendezvous with Gorkon's ship, the IKS Kronos One and escort the Chancellor to Earth for the negotiations.
Not everyone was pleased with the idea of peace between the Klingon Empire and the Federation; high-ranking officials in both of the two governments, as well as the Romulans, sought to prevent a peace accord. Gorkon's ship was attacked by a prototype Klingon Bird of Prey that could fire while cloaked. The attack knocked out the battle cruiser's artificial gravity system, leaving the Klingons aboard almost completely helpless. Two Federation personnel beam aboard Kronos One and assassinated Gorkon. Captain Kirk and Dr. McCoy transported over to the Klingon ship to assist with damage control, and McCoy tried unsuccessfully to resuscitate the Chancellor. Everyone believed the Enterprise was the ship that attacked, and Kirk and McCoy were arrested for the assassination.
Gorkon’s last words were spoken to Kirk: "Don't let it end this way, Captain." His daughter, Azetbur succeeded him as Chancellor.