government forces; loyalist army
Refers to the army of the ruling government, especially in historical contexts such as the Boshin War. Often contrasted with 賊軍 (rebel army). The proverb 勝てば官軍、負ければ賊軍 (the winner becomes the government army, the loser the rebel army) illustrates the political nature of the term.
See also: 勝てば官軍、負ければ賊軍 · 賊軍
In the Boshin War, the government forces defeated the rebel army.
There is a saying: 'If you win, you are the government army; if you lose, you are the rebel army.'