Mandalorians are a subspecies of Humans native to the planet Mandalore. They first appeared in the Pocket Universe relatively recently, around Year 11,950 in the New Shi'ar Calendar. Apparently, a series of Wormholes connected Earth in the Old Universe with Mandalore.
Mandalorians reproduce by cloning and have a militaristic society like the Sontarans. Unlike the Sontarans, Mandalorians can be either male or female.
Some Mandalorians have exhibited the ability to use Psionics, and are the only humans able to use such powers of the mind.
On Earth, the ancestors of the Mandalorians were cloned to serve as soldiers in the United Earth Regime's war against the robotic, human-hating Cylons on that world.
In the Pocket Universe, the Mandalorians have only one true enemy, the local version of the Cylons based on New Cylon. Mandalorians raids into the Cylon Sector are frequent, and cooperation with the Rebel Alliance is common.
Some Mandalorians have decided to follow the path of Orks in hiring themselves out as mercenaries.