Aylwin served as president from 1990 until 1994. He oversaw Chile's transition to democracy under the center-right Christian Democratic Party.
Although Aylwin initially praised Pinochet's armed forces after a military coup d'etat in 1973, stating the military saved "the country from descending either into civil war or Communist tyranny," he later became one of the Pinochet regime's fiercest critics.
Pinochet stepped down after a failed vote in which he asked Chileans if they wanted him to lead for another eight years. Aylwin led the victorious "no" campaign against Pinochet.
After winning the first election following the dictatorship, Aylwin set up the Rettig Commission, which was designed to investigate human rights abuses under Pinochet. The commission acted warily, as the military still maintained significant power.
Although there was pressure from the military since the commission's installment, Aylwin pushed forth a mandate that drew up a comprehensive list of thousands of people who were kidnapped, tortured or killed during the 1973-90 Pinochet dictatorship -- regarded as Aylwin's greatest achievement as president.
Pinochet died at the age of 91 from heart complications in December 2006.