Central City is the official capital and also the seat of government in Amestris. The National Central Library, Central Command, the 5 National Laboratories, and Amestris' Parliament are all located in Central. Aside from its symbol as a military headquarters, Central is also a bustling metropolis and arguably Amestris' largest city, complete with nearly everything Amestrian society has to offer as well as a lasting and rarely disturbed sense of peace created by its proximity to the government's imposing presence. After the events in the eastern regions of Amestris and the Elrics' excursion to the southern region, much of the Fullmetal Alchemist story takes place in Central, as it also serves as the Homunculi's home base, the heart of which is located deep beneath Central Command Headquarters.
Central City becomes the main target of Roy Mustang's coup d'état to overthrow the corrupt government while King Bradley was supposedly injured in a "train crash" far in the east. Briggs and East City forces manage to take over the streets with the minor help from ex-soldiers and Ishvalans alike. However, it's General Olivier Armstrong and Buccaneer who lead their respective divisions in taking over Central Command successfully until Bradley makes his unexpected return - greatly complicating the struggle for Central City and indeed the country itself.
After King Bradley's and Father's defeat, Grumman becomes the new Führer-President. However, Bradley's true identity is hidden from the public and they are told that he died heroically fighting in the battle against the Homunculi.