Military Square is the oldest of the “Squares” (the others being National, Academic, Civic, and Market) and was part of the original construction of Agwilcress. The entire city used to be a military complex, but after the fall of the original capital of Cresselecapera, the area was converted to be the heart of the Seven-Star Nation. This one block of barracks and training spaces was left intact and became the headquarters of the Seven-Star Army. The only other major structures remaining from those early years are the City Walls and the Residential Block. They all share the same reddish coloring scheme.

The design of Military Square evolved from an early version of the Kylal Palace. Over time, the palace changed to the point it no longer resembled its former self. About the only thing the buildings now share is the design of the arched roof and use of arched pillars. Here’s a view of that early version:
Yeah, those are Quake-era graphics.