The Carnation Revolution was initially a military coup in Lisbon, Portugal, on 25 April 1974 which overthrew the authoritarian regime of the Estado Novo. The revolution started as a military coup organized by the Armed Forces Movement (Portuguese: Movimento das Forças Armadas, MFA) composed of military officers who opposed the regime, but the movement was soon coupled with an unanticipated and popular campaign of civil resistance. This movement would lead to the fall of the Estado Novo and the withdrawal of Portugal from its African colonies.

The name "Carnation Revolution" comes from the fact that almost no shots were fired and that when the population took to the streets to celebrate the end of the dictatorship and war in the colonies, carnations were put into the muzzles of rifles and on the uniforms of the army men. In Portugal, 25 April is a national holiday, known as Freedom Day (Portuguese: Dia da Liberdade), to celebrate the event.

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