Maria Plieseis (born Maria Wagner: 15 August 1920 - 9 January 2004) was an Austrian anti-government activist in her home region, the Salzkammergut. She married and was widowed in 1941 and joined the Communist Party (which was outlawed at the time) in 1942, and by 1947, despite having ended up in the part of Austria under American military occupation, she emerged as a high-profile Communist activist. She was listed for prosecution as a defendant at the trial which followed the (still controversial) "Bad Ischl Milk Demonstrations", but took temporary refuge in the Soviet occupation zone and thereby avoided US military justice).