She was elected in 1994, defeating UNP candidate Srima Dissanayake in the largest landslide victory in Sri Lankan history, securing 62% of the votes.

He was the only son of Sir Solomon Dias Bandaranike, the Maha Mudaliyar, the chief Ceylonese representative and advisor to the Governor of Ceylon.

Her father, S. W. R. D. Bandaranaike, played a significant role in Sri Lanka’s early post-independence politics, serving as the country’s first Cabinet Minister of Health and Local Government in 1948.

[6] As prime minister, he was responsible for putting forth significant reforms such as the nationalization of bus companies and the Port of Colombo, a prohibition on caste-based discrimination, the removal of British military bases, and the establishment of diplomatic missions with a number of Communist states.

She thereafter enrolled in a PhD program in development economics at the École Pratique des Hautes Études, Paris, where she studied from 1970 to 1973.

[12] She returned to Ceylon in 1972, where her mother had become prime minister for the second time in 1970 and launched a wide-ranging programme of socialist reform, and faced a violent communist insurrection in 1971.

[15] Her government continued the open economic policies of the UNP, with an increase in the major revenue earners; the apparel industry, foreign remittances from migrant unskilled labor, and tea exports.

[20] Early in her term, she made conciliatory moves toward the separatist Tamil Tigers (LTTE) in an attempt to end the ongoing civil war.

[22] She thereafter pursued a more military-based strategy against them launching several major offensives such as Operation Riviresa which captured the Jaffna peninsula from the LTTE.

Her government, led by Foreign Minister Lakshman Kadirgamar increased the recognition and acceptance of Sri Lanka on the international stage, which had been greatly affected by the riots and suppression of insurgency in the 1980s.

[25] She lost vision in her right eye (permanent optic nerve damage) in an assassination attempt, by the Tamil Tigers, at her final election rally at Colombo Town Hall premises on 18 December 1999.

[26] Her second term saw the civil war aggravating with her government suffering major defeats against the LTTE such as the Second Battle of Elephant Pass and Bandaranaike Airport attack.

In December 2001, her party the People's Alliance lost the parliamentary election to the UNP, and her political opponent, Ranil Wickremasinghe, became Sri Lanka's new prime minister.

In February 2002 Wickremasinghe's government and the LTTE signed a permanent ceasefire agreement, paving the way for talks to end the long-running conflict.

President Kumaratunga believed Wickremasinghe was being too lenient towards the LTTE, and in May 2003 she indicated her willingness to sack the prime minister and government if she felt they were making too many concessions to the rebels.

On 4 November 2003, while Prime Minister Wickremasinghe was on an official visit to the US, Kumaratunga prorogued Parliament and took over Defense, Interior, and Media ministries herself.

[28] However, in June 2005, the JVP left Kumaratunga's government over a disagreement regarding a joint mechanism with LTTE rebels sharing foreign aid to rebuild the tsunami-devastated Northern and Eastern areas of Sri Lanka.

Kumaratunga noted in 2007: ″I sincerely tried to reach a political consensus to solve the ethnic question, and tried to introduce a pluralistic constitution that would cater to the political aspirations of the Tamil people without dividing the country.″[32] In September 2009, Kumaratunga, on a personal visit to Kerala, India told reporters "I too care for my life.

"[33] In February 2017, Kumaratunga accepted an invitation to join the eminent international Council of Patrons of the Asian University for Women (AUW) in Chittagong, Bangladesh.

[36][37] She successfully endorsed Maithripala Sirisena as the common candidate of the opposition in the 2015 presidential election, who defeated Mahinda Rajapaksa.

In the same year, Kumaratunga supported the United National Party in the general elections to avoid Rajapaksa becoming prime minister.

[39] In the aftermath of the 2018 Maldivian presidential election it was revealed that Kumaratunga was instrumental in forming the opposition alliance against the incumbent President Abdulla Yameen.

[40] During the 2018 Sri Lankan constitutional crisis, Kumaratunga remained silent and she later claimed that she was not invited to the special convention of the SLFP on 4 December 2018.