The Government of army is called Martial Law
Martial law is the imposition of direct military control of normal civilian functions of government, especially in response to a temporary emergency such as invasion or major disaster, or in an occupied territory.[1][2]
Martial law can be used by governments to enforce their rule over the public, as seen in multiple countries listed below. Such incidents may occur after a coup d'état (Thailand in 2006 and 2014, and Egypt in 2013); when threatened by popular protest (China, Tiananmen Square protests of 1989, 2009's Iranian Green Movement that led to the takeover by Revolutionary Guards); to suppress political opposition (Poland in 1981); or to stabilize insurrections or perceived insurrections (Canada, The October Crisis of 1970). Martial law may be declared in cases of major natural disasters; however, most countries use a different legal construct, such as a state of emergency.
Martial law has also been imposed during conflicts, and in cases of occupations, where the absence of any other civil government provides for an unstable population. Examples of this form of military rule include post World War II reconstruction in Germany and Japan, the recovery and reconstruction of the former Confederate States of America during Reconstruction Era in the United States of America following the American Civil War, and German occupation of northern France between 1871 and 1873 after the Treaty of Frankfurt ended the Franco-Prussian War.
Typically, the imposition of martial law accompanies curfews; the suspension of civil law, civil rights, and habeas corpus; and the application or extension of military law or military justice to civilians. Civilians defying martial law may be subjected to military tribunal (court-martial).