The Kkore were a race of enormously tall beings originating in Grey Space, an area outside of the Milky Way. They had ventured into the galaxy previously, though this venture had led to the evolution of the Delvians.
The Kkore spent thousands of cycles planning an invasion of the Milky Way, finally launching their attack in the beginning of the 21st century (Earth calendar). After an initially devastating assault, the Kkore were defeated by a small, rag-tag armada made up of the species in the Uncharted Territories who were most immediately threatened by the invasion -- along with the help of the Delvians and their Dej-Wah ritual. It is unknown what fate befell the rest of the Kkore after this decisive defeat.
The Kkore are taken from the Farscape comics.