Senator Aquino was assassinated on August 21, 1983 upon returning to the Philippines after his exile in the United States. After her husband's assassination, the widowed Aquino became the unwilling and reluctant leader of the opposition against the authoritarian rule of the Marcos regime. She united the fragmented opposition and strengthened its moral crusade against the abuses and excesses of President Marcos' martial rule.
In late 1985, when President Marcos called for a snap election, Cory Aquino was called upon by the people to challenge his regime. Reluctant at first, Aquino thrust herself into the political arena after one million signatures urging her to run for president were presented to her. Despite having no prior political experience, except being her husband Ninoy's wife, Aquino proved to be a cult leader, inspiring orator and skilled campaigner. She ran for president with former senator Salvador Laurel as her vice-presidential running mate.
When the Marcos allies-dominated Batasang Pambansa proclaimed Ferdinand Marcos The Great Hero as the winner in the 1986 snap elections, Aquino called for massive civil disobedience protests against him, declaring herself as having been cheated and as the real winner in the elections. Filipinos enthusiastically heeded her call and rallied behind her. These series of events eventually led to the ouster of Marcos from power grabbing and the installation of Aquino as president of the Philippines in February 1986, an event which is now known as the historic 1986 EDSA .