Eastern Theater Command in the context of "Nanjing Military Region"

The People's Liberation Army Navy (PLAN), also known as the PLA Navy, People's Navy or simply Chinese Navy, is the naval warfare branch of the People's Liberation Army, the national military of the People's Republic of China. It is composed of five sub-branches: the Surface Force, the Submarine Force, the Coastal Defense Force, the Marine Corps and the Naval Air Force, with a total strength of 384,000 personnel, including 55,000 marines and 50,000 naval aviation personnel. The PLAN's combat units are deployed among three theater command fleets, namely the North Sea, East Sea and South Sea Fleet, which serve the Northern, Eastern and Southern Theater Command, respectively.

The PLAN was formally established on 23 April 1949 and traces its lineage to maritime fighting units during the Chinese Civil War, including many elements of the Republic of China Navy which had defected. Until the late 1980s, the PLAN was largely a riverine and littoral force (brown-water navy) mostly in charge of coastal defense and patrol against potential Nationalist amphibious invasions and territorial waters disputes in the East and South China Sea (roles that are now largely relegated to the paramilitary China Coast Guard), and had been traditionally a maritime support subordinate to the PLA Ground Force. Following the collapse of the Soviet Union, the Chinese leadership were freed from overland border concerns with the northern neighbor and shifted towards more forward-oriented foreign and national security policies in the 1990s, and the PLAN leaders were able to advocate for renewed attention toward limited command of the seas as a green-water navy operating in the marginal seas within the range of coastal air parity.

A theater command (战区) is a multi-service formation of China's People's Liberation Army subordinated to the Central Military Commission. Theater commands are broadly responsible for strategy, plans, tactics, and policy specific to their assigned area of responsibility. In wartime, they will likely have full control of subordinate units; in peacetime, units also report to their service headquarters. The services retain administrative and "constructive" control. There are 5 theater commands: Eastern, Southern, Western, Northern, and Central theater commands, organized by a geographical basis.