Semi-Colonials were developed for a small association of millionaires to fight mock battles from the British colonial period. The Arps were enthusiastic about the idea (they were designed to be) and enjoyed the mock battles. But rivalry between the races was contained on the battlefield; they tended to be good friends and neighbors the rest of the time.

Since the disappearance of their former masters, Semi-Colonial groups have spread to hold individual territories. Together, they hold a large territory they defend as a group. They have festivals every year where they fight mock battles, drink lots of beer, and reminisce about the "good old days" (the Victorian Colonial period, of course).

The Semi-Colonials are drawn from a variety of species.

• The Boars are based on the European wild boar, with a culture from the Boers (Dutch colonists in South Africa) late 1800s. (The boars were one of the first really bizarre Arps, being the first attempt to create a truly Centauroid creature.)
• The Boxers are based on the Boxer, with a culture from the Chinese "Boxer" secret society, circa 1900. The Boxers are a reclusive group who try to exclude all non-boxers from their territory. Only marginally associated with the Semi-Colonial "empire".
• The Brittanys are based on the Brittany Spaniel. These fearless soldier-dogs defend Honor and Empire from revolting natives. Brave and loyal, they absolutely insist on tea and crumpets at four in the afternoon. They form what little central government the Semi-Colonials have.
• The Hareabs are based on the Jack rabbit, with a culture from Composite North African Cultures. The Hareabs form several different "tribes", some of which do battle with the Brittanys, though mostly their opponents are the French Ferret Legion.
• The Zuluroos are based on the Red Kangaroo, with a culture from the Tribal Zulu, mid to late 1800s. The Zuluroos are much darker furred than their genetic ancestors, in keeping with their Pseudo-culture. They organize militarily into historical Zulu regiments, though with some slight alterations in the names such as the umBouceambi. Fond of boxing as a sport.