The Imperium of Mandalore, also called the Mandalore Protectorates and most commonly referred to simply as Mandalore, was the feudal interstellar nation of the Mandalorian people which was centralized in the Trans-Hydian Sectors of the Outer Rim. It was a martial state, born in the midst of the Hydian Wars and molded by the rule of the mand'alors into one of the great military powers of the galaxy.
When the Great Chaos erupted across the Outer Rim Territories and utter bedlam threatened to engulf the Trans-Hydian worlds, a coalition of tribes and coverts launched a crusade to repel the ruinous forces and protect vulnerable worlds in the region. Those they assisted came to revere the Mandalorians to such a degree that they gifted the warriors lands and fortresses from which to operate as well as the resources to sustain their campaigns. These tributaries provided the foundations for Mandalore to gain suzerainty across a vast swath of star systems over the course of a few decades.
The Imperium of Mandalore was officially founded during the reign of Mand'alor the Unifier, via the signing of the Treaty of Nevarro in 13 ABY. It's society was built upon the code of the Mandalorian Creed, with the principles of public service, honor, loyalty, and strength being central pillars of the culture. For the first 20 years of the Imperium's existence, its capital was based on Concordia but was eventually moved to the surface of planet Mandalore after a period of terraforming left it suitable for habitation. The Mandalorians' role as peacekeepers in the region made all but the most daring pirates, slavers, and warlords wary of operating in the Trans-Hydian for fear of drawing the ire of the supercommandos.