Sri Lanka is the oldest continually Buddhist country in the world. The religion was introduced in Srilanka in 2nd century BC by Mahinda-the son of Indian Emperor Ashoka-during the reign of King Devanampiya Tissa. Later on Ashoka's daughter Sanghamitta brought southern branch of the original Bodhi tree-under which Buddha attained enlightenment. The branch was planted at Anuradhapura and is today considered very sacred by Buddhists all over the world.
In the 1st century AD during the reign of King Vatta Gamini the Buddhist monks assembled in Aloka-Vihara and wrote down the Tripitaka, the three baskets of the Teachings, known as the Pali scriptures for the first time. Sri Lankan monks played a vital role in spreading Buddhism to South-east Asia and other parts of the world.
Following the advent of Portuguese in Sri Lanka in 16th century, Buddhism began to decline. Portuguese conquered Srilanka and savagely persecuted Buddhism, as did the Dutch who followed them. When the British won control at the beginning of the 19th century Buddhism was at its lowest ebb and Christianity was fast spreading its roots. But against all expectations the monastic and lay community brought about a major revival from about 1860 onwards, a movement that went hand in hand with growing nationalism.
Buddhism has two major schools-Theravada and Hinyana. In Sri Lanka Theravada school is followed. Theravada Buddhism in Sri Lanka itself can be divided into three different sects.
In the 18th century, the official line of monastic ordination had been broken since monks at that time no longer knew the Pali tradition. The Kandyan king invited then the Theravada monks from Thailand to ordain Sinhalese novices; it was set up later as a reformed sect that enlivened study and proliferation of Theravada Buddhism in Sri Lanka.
s This sect was initiated by members of rising low-country castes discontent with monopoly over the monastic community by the upper castes in the 19th century. The sect was subsequently slit along the caste lines.
This sect was established in the late nineteenth century as a result of disputes over some points of doctrine and the practice of meditation.