The Empire is the main setting of most of the events in Akame ga Kill!.
The Empire is a superpower that has lasted for over 1000 years, boasting vast territories and resources. Its capital city is enormous, covering roughly 200,000 sq. kilometers, and is encircled on all sides by a huge wall. The capital’s various districts are separated by large canals in which trade ships run through. Beyond the capital, the country seems to be mostly rural with an unknown number of cities and villages spread throughout. The exact size of the Empire itself has yet to be revealed. Three other countries border the Empire to the north, south, and west while the Empire’s eastern boundary is the coastline of a great ocean.
At its founding, the Empire had nearly limitless resources and some of the best minds in the world, with the First Emperor having absolute authority. At some point during this period the Emperor, wishing to ensure that his nation would last forever, ordered the creation of the Teigu. These weapons greatly increased the power of the Empire’s military and it is heavily implied that their introduction resulted in a great surge of imperial expansionism.
Several hundred years later the Empire experienced a huge civil war. Little has been revealed about it but it is known that almost half of the Teigu were lost during this conflict as a result.