Peace talks yielded nothing and in 2006, Mahinda turned to Gotabaya, a retired infantry officer whom he had made defence secretary, to draw up a plan to defeat the Tigers once and for all.
The Tigers eventually conceded defeat in 2009 following a ferocious government offensive in which the United Nations has estimated as many as 40,000 Tamil civilians were killed in the final few months of the war alone.
The government said the rebels kept thousands of civilians as human shields, exacerbating the death toll.
The United Nations believes up to 100,000 people were killed over the duration of the conflict and in 2021, its Human Rights Council adopted a resolution that gave the human rights chief's office new staff, powers and a $2.8 million budget to look at Sri Lanka's war with a view to future prosecutions.