{{unsourced, date=February 2021
A ministry of defence or defense (see
spelling differences
Despite the various English dialects spoken from country to country and within different regions of the same country, there are only slight regional variations in English orthography, the two most notable variations being British and American ...
), also known as a department of defence or defense, is an often-used name for the part of a
government
A government is the system or group of people governing an organized community, generally a state.
In the case of its broad associative definition, government normally consists of legislature, executive, and judiciary. Government is a ...
responsible for matters of defence, found in states where the government is divided into ministries or departments. Such a department usually includes all branches of the
military
A military, also known collectively as armed forces, is a heavily armed, highly organized force primarily intended for warfare. It is typically authorized and maintained by a sovereign state, with its members identifiable by their distinct ...
, and is usually controlled by a defence minister, minister of defence, or secretary of defense.
Historically, such departments were referred to as a Ministry of War or Department of War, although such departments generally had authority only over the army of a country, with a separate department governing other military branches. Prior to
World War II
World War II or the Second World War, often abbreviated as WWII or WW2, was a world war that lasted from 1939 to 1945. It involved the vast majority of the world's countries—including all of the great powers—forming two opposin ...
, most "Ministries of War" were Army ministries, while the Navy and the Air Force, if it existed as a separate branch, had their own departments. As late as 1953, for example, the
Soviet Union
The Soviet Union,. officially the Union of Soviet Socialist Republics. (USSR),. was a transcontinental country that spanned much of Eurasia from 1922 to 1991. A flagship communist state, it was nominally a federal union of fifteen national ...
had a "Ministry of War" alongside a "Ministry of the Navy".
The tendency to consolidate and rename these departments, and to coordinate until then mostly separate components of defence (air, land, navy) arose after World War II.