The Empire of Vietnam was a short-lived puppet state of Imperial Japan governing the former French protectorates of Annam and Tonkin between March 11 and August 25, 1945. At the end of its rule, the empire also successfully reclaimed Cochinchina as part of Vietnam.

A puppet state, puppet régime, puppet government or dummy government is a state that is de jure independent but de facto completely dependent upon an outside power and subject to its orders. Puppet states have nominal sovereignty, except that a foreign power effectively exercises control through economic or military support. By leaving a local government in existence the outside power evades all responsibility, while at the same time successfully paralysing the local government they tolerate.