Sinhala only

The Sinhala Only Act, formally the Official Language Act No. 33 of 1956, was an act passed in the Parliament of Ceylon in 1956. The act replaced English as the official language of Ceylon with Sinhalese. The act failed to give official recognition to Tamil, which had not received official recognition before.

Sinhalese is the language of Sri Lanka's majority Sinhalese people, who accounted for around 70% of the country's population at that time. Tamil is the first language of Ceylon's three largest minority ethnic groups, the Indian Tamils, Sri Lankan Tamils and Moors, who together accounted for around 29% of the country's population.

The act was controversial as supporters of the act saw it as an attempt by a community that had just gained independence to distance themselves from their colonial masters, while its opponents viewed it as an attempt by the linguistic majority to oppress and assert dominance on minorities. The Act symbolizes the post independent majority Sinhalese to assert its Sri Lanka's identity as a nation state, and for Tamils, it became a symbol of minority oppression and a justification for them to demand a separate nation-state, Tamil Eelam, which was a factor in the emergence of the decades-long Sri Lankan Civil War.

Under the British Empire, English was the language of rule in Ceylon (now known as Sri Lanka). Until the passage of the Free Education Bill in 1944, education in the English language was the preserve of the subaltern elite and the ordinary people had little knowledge of it. A disproportionate number of English-language schools were located in the mostly Tamil-speaking north. Thus, English-speaking Tamils held a higher percentage of coveted Ceylon Civil Service jobs, which required English fluency, than their share of the island's population.

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