Answer
When Konstantinos Karamanlis resigned as prime minister of Greece in 1980, Andreas Papandreou took over the position. Papandreou was a member of the Panhellenic Socialist Movement (PASOK), and his election marked the first time that a socialist had been elected prime minister of Greece. Papandreou served as prime minister for two terms, from 1981 to 1989 and from 1993 to 1996.