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government forces; loyalist army
官軍は幕府軍を破った。
The imperial forces defeated the shogunate army.
官軍の勝利で新政府が樹立された。
The victory of the imperial forces led to the establishment of a new government.
明治維新の際、官軍が各地を制圧した。
During the Meiji Restoration, the imperial forces took control of various regions.