Kelvans predicted rising radiation levels in Andromeda would render their galaxy uninhabitable to their species within ten millennia. In the mid-1960s, the Kelvan Empire dispatched multi-generational starships to their neighboring galaxies, searching for new territories suitable for conquest and occupation. A Kelvan expedition arrived in the Milky Way Galaxy in 2268. The Last Unicorn Games RPG book All Our Yesterdays states that in the 123rd century the Kelvan race invaded the Milky Way Galaxy.