In military dictatorships, or governments which have arisen from coups d'état, the position of commander-in-chief is obvious, as all authority in such a government derives from the application of military force; occasionally a power vacuum created by war is filled by a head of state stepping beyond his or her normal constitutional role, as King Albert I of Belgium did during World War I. In these and in revolutionary regimes, the head of state, and often executive ministers whose offices are legally civilian, will frequently appear in military uniform.