English was the official language under the British and remained so until 1956, when Sinhala became the nation's one official language. This measure was bitterly opposed by the Tamil minority. Riots, disorders, and dissension grew, leading to a Tamil civil disobedience campaign and a temporary state of emergency. The 1978 constitution recognized Sinhala as the official language but also recognized Tamil as a national language. Sinhala is a member of the Indo-Aryan subgroup of the Indo-European language family, related to Pali. Tamil is a Dravidian language spoken in northern and eastern Sri Lanka and in southern India. It became an official language in December 1988. In 1999, Sinhala was spoken by approximately 74% of the population; Tamil was spoken by 18%. English is also commonly used in government and is spoken by about 10% of the population.