The Kelvans were a highly intelligent race. The Kelvans lived on the planet Kelva located in the Andromeda Galaxy. In their natural state, Kelvans were beings with a 100 tentacle-like limbs and their minds were capable of performing numerous tasks simultaneously with their limbs.
They would conquer other races. They posessed technology to control their subjects.
When they realized their galaxy would die in 10 millennia. They decided to send members to other galaxies to conquer other worlds.
Their ships are faster then Starfleet's. It still took them 300 years to reach the Milky Way. One ship crashed into the galactic barrier. The ship was destroyed and only five Kelvans survived and went on to comendeer the U.S.S. Enterprise. It was at this time when they experienced emotions for the first time.
Captain James T. Kirk convinced the Kelvans to work with the Federation to establish new worlds. A drone ship was sent back to Kelva detailing the events.