The Movement of Democratic Unity (Portuguese: Movimento de Unidade Democrática or MUD) was a quasi-legal platform of Portuguese democratic organizations that opposed the authoritarian regime of António de Oliveira Salazar and was founded in October 1945.
In hopes of improving the image of the regime in Western circles, the government authorized some limited democratic openings, such as the creation of the MUD, in October 1945.
The opposition groups were already organized in the Movement of National Antifascist Unity (MUNAF), which was quickly replaced by the MUD.
The MUD quickly developed a strong structure, based on local committees at district, parish and neighborhood level.
Initially, MUD was dominated by the moderate elements of the opposition, but soon the Portuguese Communist Party became the main force inside the Movement.