The Carnation Revolution and Independence in 1975

By the early 1970s Portugal was fighting three colonial wars that consumed a large share of its budget and required young men to serve years in the army; many emigrated to avoid conscription. In February 1974 General António de Spínola published a book arguing the wars could not be won militarily. On 25 April 1974 the Armed Forces Movement, a group of mostly junior officers, overthrew Salazar's successor Marcelo Caetano almost without bloodshed.

A song broadcast on the radio was the signal to move, and civilians placed carnations in soldiers' rifles, giving the revolution its name. The new government moved to end the wars. Portugal recognized Guinea-Bissau in September 1974; Mozambique became independent on 25 June 1975, Cape Verde and São Tomé and Príncipe in July, and Angola on 11 November 1975, as its civil war was already under way. Hundreds of thousands of settlers, called retornados, moved to Portugal. The revolution shows how colonial wars could transform the colonizing country itself.