The name "Carnation Revolution" comes from the fact no shots were fired and when the population started descending the streets to celebrate the end of the war in the colonies, carnation flowers were put on the guns' ends and on the uniforms. These events effectively changed the Portuguese regime from an authoritarian dictatorship (the Estado Novo) into a democracy, and produced enormous social, economic, territorial, demographic, and political changes in the country, after two years of a transitional period known as PREC (Processo Revolucionário Em Curso, or On-Going Revolutionary Process), characterized by social turmoil and power disputes between left- and right-wing political forces.
via en.wikipedia.org