Sri Lanka, historically known as Ceylon, and officially the Democratic Socialist Republic of Sri Lanka, is an island country in South Asia. It lies in the Indian Ocean, southwest of the Bay of Bengal, separated from the Indian peninsula by the Gulf of Mannar and the Palk Strait. It shares a maritime border with the Maldives in the southwest and India in the northwest. Sri Lanka has a population of approximately 22 million and is home to several cultures, languages and ethnicities. The Sinhalese people form the majority of the population, followed by the Sri Lankan Tamils, who are the largest minority group and are concentrated in northern Sri Lanka; both groups have played an influential role in the island's history. Other long-established groups include the Moors, Indian Tamils, Burghers, Malays, Chinese, and Vedda. Sri Lanka's documented history goes back 3,000 years, with evidence of prehistoric human settlements dating back 125,000 years. The earliest known Buddhist writings of Sri Lanka, known collectively as the Pali Canon, date to the fourth Buddhist council, which took place in 29 BCE. Also called the Pearl of the Indian Ocean, or the Granary of the East, Sri Lanka's geographic location and deep harbours have made it of great strategic importance, from the earliest days of the ancient Silk Road trade route to today's so-called maritime Silk Road. Because its location made it a major trading hub, it was already known to both East Asians and Europeans as long ago as the Anuradhapura period. During a period of great political crisis in the Kingdom of Kotte, the Portuguese arrived in Sri Lanka and sought to control its maritime trade, with a part of Sri Lanka subsequently becoming a Portuguese possession. After the Sinhalese-Portuguese war, the Dutch colonial empire and the Kingdom of Kandy took control of those areas. Dutch Ceylon was taken by the British Empire, which extended control over the whole island, colonising it as British Ceylon from 1815 to 1948. A national movement for political independence arose in the early 20th century, and 1948, Ceylon became a dominion. It was succeeded by the republic of Sri Lanka in 1972. Sri Lanka's more recent history was marred by the 26-year Sri Lankan Civil War, which began in 1983 and ended in 2009, when the Sri Lanka Armed Forces defeated the Liberation Tigers of Tamil Eelam. Sri Lanka is a developing country, ranking 78th on the Human Development Index. It is the highest-ranked South Asian nation in terms of development and has the second-highest per capita income in South Asia. The country has had a long history of engagement with modern international groups; it is a founding member of the SAARC, the G77 and the Non-Aligned Movement, as well as a member of the United Nations and the Commonwealth of Nations.