As a result of their interfering with time - including an attempt to prevent the Suliban species from forming - the Na'kuhl were hunted by temporal agents from the 31st century Federation. At one point they managed to seek refuge on Earth in the 1940s, but became trapped there, with no temporal vehicles or other means of escape. There they interfered with history once again by allying with the Earth nation of Germany; creating an alternative timeline in which most of the western hemisphere was under German control in the 20th century. They attempted to use Earth resources to build a temporal conduit mechanism that could end their exile and allow them to continue their war for galactic dominance. Although they actually succeeded in this; temporal agents were able to track down the origin of the conduit and send Earth Starfleet officer Captain Archer back in time to destroy the conduit and restore the original timeline; which he succeeded in doing. It is implied that with the destruction of the Na'kuhl the Temporal Cold War came to an end, but it isn't clear whether the group stranded on 1944 Earth represented the only members of the species, the only ones with time travel capabilities or simply a group of renegades.