Sri Lanka has a multi ethnic and multi religious population.
The majority of the people in Sri Lanka are Sinhalese. This ethnic group of is said to have originated in the north-east section of India and later settled to Sri Lanka. They speak Sinhala , an Indo-European language and number approximately 15 million people.
The largest ethnic minority in Sri Lanka are the Tamils. Their language is Tamil and it is a Dravidian based language.
English is spoken by around 10% of the population and 8% speak other languages.
About 70% of the population practices Buddhism.
Other major religions include Hinduism, Christianity and Islam.
The government is officially a republic and the capitol is Colombo.
Sadly, Sri Lanka has been going through some terrible times in regards to religious and cultural freedoms since 1983. Civil war has been active and ever increasing up into the present time. I am going to defer to other sources to provide details. In short, the two largest ethnic groups do not like each other and people have been treating each other horribly...in ways that word cannot do justice.