Shortly after independence in 1948, G.G. Ponnambalam and his All Ceylon Tamil Congress joined D.S. Senanayake's moderate, western-oriented United National Party led government which led to a split in the Tamil Congress.
S.J.V. Chelvanayakam, the leader of the splinter Federal Party (FP or Illankai Tamil Arasu Kachchi), contested the Ceylon Citizenship Act, which denied citizenship to Tamils of recent Indian origin, before the Supreme Court, and then in the Privy council in England, but failed to overturn it.
The FP eventually became the dominant Tamil political party.
In response to the Sinhala Only Act in 1956, which made Sinhala the sole official language, Federal Party Members of Parliament staged a nonviolent sit-in (satyagraha) protest, but it was violently broken up by a mob.
The FP was blamed and briefly banned after the riots of May–June 1958 targeting Tamils, in which many were killed and thousands forced to flee their homes.
Another point of conflict between the communities was state sponsored colonisation schemes that effectively changed the demographic balance in the Eastern Province, an area Tamil nationalists considered to be their traditional homeland, in favour of the majority Sinhalese.

In 1972, a newly formulated constitution removed section 29(2) of the 1947 Soulbury constitution that was formulated to protect the interests of minorities.
Also, in 1973, the Policy of standardization was implemented by the Sri Lankan government, supposedly to rectify disparities in university enrolment created under British colonial rule.
 The resultant benefits enjoyed by Sinhalese students also meant a significant decrease in the number of Tamil students within the Sri Lankan university student population.

Shortly thereafter, in 1973, the Federal Party decided to demand a separate Tamil state.
In 1976 they merged with the other Tamil political parties to become the Tamil United Liberation Front (TULF).
  By 1977 most Tamils seemed to support the move for independence by electing the Tamil United Liberation Front overwhelmingly.
The elections were followed by the 1977 riots, in which around 300 Tamils were killed.
There was further violence in 1981 when an organised Sinhalese mob went on a rampage during the nights of 31 May to 2 June, burning down the Jaffna public library—at the time one of the largest libraries in Asia—containing more than 97,000 books and manuscripts.
Shortly after independence in 1948, G.G. Ponnambalam and his All Ceylon Tamil Congress joined D.S. Senanayake's moderate, western-oriented United National Party led government which led to a split in the Tamil Congress. S.J.V. Chelvanayakam, the leader of the splinter Federal Party (FP or Illankai Tamil Arasu Kachchi), contested the Ceylon Citizenship Act, which denied citizenship to Tamils of recent Indian origin, before the Supreme Court, and then in the Privy council in England, but failed to overturn it. The FP eventually became the dominant Tamil political party. In response to the Sinhala Only Act in 1956, which made Sinhala the sole official language, Federal Party Members of Parliament staged a nonviolent sit-in (satyagraha) protest, but it was violently broken up by a mob. The FP was blamed and briefly banned after the riots of May–June 1958 targeting Tamils, in which many were killed and thousands forced to flee their homes. Another point of conflict between the communities was state sponsored colonisation schemes that effectively changed the demographic balance in the Eastern Province, an area Tamil nationalists considered to be their traditional homeland, in favour of the majority Sinhalese.
In 1972, a newly formulated constitution removed section 29(2) of the 1947 Soulbury constitution that was formulated to protect the interests of minorities. Also, in 1973, the Policy of standardization was implemented by the Sri Lankan government, supposedly to rectify disparities in university enrolment created under British colonial rule.  The resultant benefits enjoyed by Sinhalese students also meant a significant decrease in the number of Tamil students within the Sri Lankan university student population.
Shortly thereafter, in 1973, the Federal Party decided to demand a separate Tamil state. In 1976 they merged with the other Tamil political parties to become the Tamil United Liberation Front (TULF).   By 1977 most Tamils seemed to support the move for independence by electing the Tamil United Liberation Front overwhelmingly. The elections were followed by the 1977 riots, in which around 300 Tamils were killed. There was further violence in 1981 when an organised Sinhalese mob went on a rampage during the nights of 31 May to 2 June, burning down the Jaffna public library—at the time one of the largest libraries in Asia—containing more than 97,000 books and manuscripts.
Sri Lankan Tamils