The Mrrshan are the second alien race Humanity has contacted, the native sapient race of Yileria, a planet in the Fieras system. Yileria has a roughly similar size and gravitational pull to Earth, but has significantly lower hydrographic coverage, with a relatively poor ecosystem concentrated in the rainy valleys surrounding Yileria's landlocked seas. The Mrrshan themselves are obligate carnivore predators native to the equatorial plains surrounding the largest sea on Yileria, who developed sophisticated cooperative behaviors to take down larger prey animals. Mrrshan eyesight and reflexes are superb, and still-powerful predatory instincts mean that recreational hunting on wildlife preserves, training stealth, tracking, and marksmanship, is an extremely common pasttime amongst Mrrshan. By now all the fertile regions of Yileria are inhabited by Mrrshan, with smaller towns even in the deep inland deserts of the planet.

The High Queendom is a relatively recent historical innovation in Yileria, only being established in any form shortly before the start of the FTL travel era in Mrrshan history within the past three centuries. A wide array of differing nation-states dominated Mrrshan politics at the time, the most common form of which were monarchies of relatively limited internal power held in check by the historically-established pattern of revolt against abusive rulers. Despite the relatively light hand of these nation-states, interterritorial warfare was common, with rulers unwilling to accept slights from rivals and with strong popular support for vengeance against insults. An escalating cycle of warfare between multiple factions threatened to spill over into full-scale thermonuclear war, when the first of the High Queens, Selara, ruler of a hitherto minor nation which had thus far maintained good relations with its neighbors, developed a plan. Selara approached neighboring rulers, one by one, and offered this: a neutral and impartial court of appeal that could deliver justice, and arbitration of existing conflicts, lest current wars destroy Yileria's civilisation. Selara's unsurpassed reputation for honesty and fairness won surprising support amongst many rulers. Those who warred against Selara's vassals were forced to submit by her growing empire, held together by the trust its subject rulers had for the new High Queen.

The contract of service and fealty for the member states of the High Queendom in exchange for protection and justice remains strong, with only the continued trust of the High Queen's vassals for their ruler holding the empire together. Forced labor and slavery of any sort does not exist in the High Queendom, which has widespread popular support and an extremely broad-based pool of military-qualified individuals amongst the general population. Hunting and small-unit military games teach many relevant skills to the population, and Mrrshan sharpshooters, commandoes, and small-unit leaders are perhaps the finest in the known galaxy. Some military analysts believe that, person for person, Mrrshan surface forces are as dangerous as anything fielded by the Bulrathi Empire, and recruited from a far broader free population. Commerce is predominantly private, but the corporate form is uncommon, with most commercial ventures maintaining direct management by single owners who rely on developing bonds of personal loyalty with employees. Religion is varied, but the dominant religious tradition in modern days worships a polytheistic pantheon ruled by the Sun Goddess, viewed as one who grants life and renewal to the world.

The High Queendom is hard-pressed by its war against the Klackons, who were earlier into space, control a somewhat wider territory, and have a formidable industrial base. Mrrshan border fortifications have been completely compromised, although Her Majesty's Royal Navy has thus far managed to hold Mrrshan territory and break blockades. Whether the situation is sustainable for the High Queendom remains uncertain, but the High Queendom still maintains hundreds of millions of armed Mrrshan willing to fight and die to protect their homes against invasion by the Klackon.