The Liberation Tigers of Tamil Eelam (LTTE) (Tamil: தமிழீழ விடுதலைப் புலிகள், romanized: Tamiḻīḻa viṭutalaip pulikaḷ, Sinhala: දෙමළ ඊළාම් විමුක්ති කොටි, romanized: Damiḷa īḷām vimukthi koṭi, also known as the Tamil Tigers) was a Tamil militant organization that was based in northeastern Sri Lanka. Its aim was to secure an independent state of Tamil Eelam in the north and east in response to the state policies of successive Sri Lankan governments that were widely considered to be discriminatory towards the minority Sri Lankan Tamils, as well as the oppressive actions—including anti-Tamil pogroms in 1956 and 1958—carried out by the majority Sinhalese.Founded in May 1976 by Velupillai Prabhakaran, the LTTE was involved in armed clashes against the Sri Lankan government and armed forces. Oppression against Sri Lankan Tamils continued by Sinhalese mobs, notably during the 1977 anti-Tamil pogrom and the 1981 burning of the Jaffna Public Library. Following the week-long July 1983 anti-Tamil pogrom carried out by Sinhalese mobs that came to be known as Black July, the LTTE's escalation of intermittent conflict into a full-scale nationalist insurgency began, which started the Sri Lankan Civil War. By this time, the LTTE was widely regarded as the most dominant Tamil militant group in Sri Lanka and among the most feared guerrilla forces in the world, while Prabhakaran's status as a freedom guerrilla fighter led to comparisons to revolutionary Che Guevara by global media, though Prabhakaran's actions were also widely viewed as terroristic.The LTTE has been designated as a terrorist organisation by 33 countries, including the European Union, Canada, the United States, and India.LTTE is noted by many academics for the popularization of the suicide vest as a weapon. Though the group did not invent suicide bombing, they perfected the use of suicide vest attacks, which are now used by many current terrorist organisations.Initially starting out as a guerrilla force, the LTTE increasingly came to resemble that of a conventional fighting force with a well-developed military wing that included a navy, an airborne unit, an intelligence wing, and a specialised suicide attack unit. In particular, India's relationship with the LTTE was complex, as it went from initially supporting the organisation to engaging it in direct combat through the Indian Peace Keeping Force (IPKF), owing to changes in the former's foreign policy during the phase of the conflict. The LTTE gained global notoriety for using women and children in combat and carrying out a number of high-profile assassinations, including former Indian Prime Minister Rajiv Gandhi in 1991 and Sri Lankan President Ranasinghe Premadasa in 1993.

Over the course of the conflict, the LTTE frequently exchanged control of territory in the north-east with the Sri Lankan military, with the two sides engaging in intense military confrontations. It was involved in four unsuccessful rounds of peace talks with the Sri Lankan government and at its peak in 2000, the LTTE was in control of 76% of the landmass in the Northern and Eastern provinces of Sri Lanka. Prabhakaran headed the organisation from its inception until his death in 2009. Between 1983 and 2009, more than 80,000 were killed in the civil war, of which many were Sri Lankan Tamils. 800,000 Sri Lankan Tamils also left Sri Lanka for various destinations, including Europe, North America, and Asia.