The Brass Legions are the principal standing military forces of the City of Brass. They defend the city and its dependent territories, hold major fortifications, protect strategically important Vergeways and trade routes, suppress threats that exceed the capacity of local authorities, and conduct conventional campaigns against rival powers in Xathoryn. Their existence reflects the scale of a city-state wealthy enough to attract invasion and ambitious enough to require military force far beyond its walls.
The Legions are a permanent professional institution rather than an army assembled only when war begins. Their command structure, logistics, engineering, supply systems, and battlefield doctrine have developed through centuries of conflict with other sophisticated Xathoryn states. Individual Sultans have expanded, reduced, reorganized, or favored particular commands according to political circumstances, so neither the precise size nor internal arrangement of the Legions has remained constant across their history.
Military command is also a route to political influence. Efreeti noble houses compete for prestigious appointments, supply contracts, and relationships with successful officers, while the Sultan must balance the usefulness of powerful commanders against the danger of allowing any one military network to become indispensable. Veterans can carry considerable social standing after leaving active service, particularly when their careers involved important victories or the defense of major planar routes.
The Brass Legions are designed for sustained military operations. They can hold territory, besiege cities, defend infrastructure, and fight organized enemies on a scale that mercenary bands or noble retainers cannot easily match. Exceptional threats are more often assigned to the Crownfire, while politically sensitive expeditions beyond Xathoryn historically created opportunities for independent organizations such as the Brass Blades.