Leader of the Kelownan people on the planet Langara, First Minister Velis was his nation's equivalent of a President. Velis's priority is to his nation, and its safety from and triumph over the rival nations of Terrania and the Andari Federation. He approved the development and testing of a naquadria bomb, a weapon of mass destruction, which he eventually ordered to be used in a preemptive first strike against Kelowna's enemies -- which the government believed were planning to attack.
Velis also sent Ambassador Dreylock, Commander Hale and Dr. Kieran to Earth, where Jonas Quinn had defected to several months earlier. Their mission was to negotiate access to Earth's more advanced military technology. When SG-1 returned to Kelowna, Velis suprised Jonas by welcoming him home -- and asking him to help them secure Earth's technology. He also asked Quinn to keep an eye on his former mentor, Dr. Kieran, who was going insane due to his exposure to naquadria. Velis even offered to allow Jonas to return home permanently, where he would be reinstated to his position and have his betrayal forgiven.
When the Goa'uld Anubis discovered Kelowna and its rich supply of naquadria, First Minister Velis was executed by the occupying Jaffa force, under the command of Herak. He was succeeded as First Minister by Dreylock.
Shadow Play - First Minister Velis welcomes Jonas Quinn back to Kelowna, not as a traitor, but as one who can help them gain access to Earth's more advanced technology.
Homecoming - SG-1 learns that Velis was killed when Anubis's forces arrived on Kelowna.