The Abhayagiri Dagaba is situated in Anuradhapura. It is one of the most extensive ruins in the world and one of the most sacred Buddhist pilgrimage cities. Historically it was a great monastic centre as well as a royal capital, with magnificent monasteries rising to many stories, roofed with gilt bronze or tiles of burnt clay glazed in brilliant colors. To the north of the city, encircled by great walls and containing elaborate bathing ponds, carved balustrades and moonstones, stood “Abhayagiri”, one of seventeen such religious units in Anuradhapura and the largest of its five major viharas. Surrounding the humped dagaba, Abhayagiri Vihara was a seat of the Northern Monastery, or Uttara Vihara.
The term “Abhayagiri Vihara” means not only a complex of monastic buildings, but also a fraternity of Buddhist monks, or Sangha, which maintains its own historical records, traditions and way of life. Founded in the second century B.C., it had grown into an international institution by the first century of this era, attracting scholars from all over the world and encompassing all shades of Buddhist philosophy. Its influence can be traced to other parts of the world, through branches established elsewhere. Thus, the Abhayagiri Vihara developed as a great institution vis‑a‑vis the Mahavihara and the jetavana Buddhist monastic sects in the ancient Sri Lankan capital of Anuradhapura.
It is recorded in the chronicles that Abhayagiri was established by King Vattagamini Abhaya(Valagamba), during the period of his second reign, from 89 to 77 B.C.. A young Brahmin named Tiya (Tissa) declared war against him. Tiya was deluded by the prophecy of another Brahmin that was destined to be king. Before the arrival of Mahinda Thera who brought Buddhism to the island, Brahmins held the highest place in society. After the establishment of the Bhikkhu order on the island, however, they lost their supremacy, and were replaced by the Buddhist Sangha. Some Brahmins converted to Buddhism, while others revolted. Tiya, who enjoyed the support of his community, lived both in and outside of Sri Lanka, and was therefore very powerful.