Mahavansa/Chapter 20 tells ...Devanampiyatissa, king of Lañkä, rich in merit and insight, caused to be carried out, even in his first year, as a friend to virtue, and his whole life through he heaped up works of merit. Our island flourished under the lordship of this king; forty years did he hold sway as king. After his death, his younger brother since there was no son, the prince known by the name Uttiya held sway piously as king. Ten years did king Uttiya reign.
Mahavansa/Chapter 20 tells ...Mahinda passed away into nirvana at Cetiya-mountain in the eighth year of king Uttiya on the eighth day of the bright half of the month Assayuja. When king Uttiya heard this he went thither andhad paid homage to the thera and arranged Mahinda's last journey and funeral rites.
Mahavansa/Chapter 20 tells ...The theri Samghamitta passed away into nirvana, being fifty-nine years old, in the ninth year of this same king Uttiya, while she dwelt in the peaceful Hatthalhaka-convent. And for her also, as for the thera, the king commanded supreme honours of burial a week through, and the whole of Lanka was adorned as for the thera Mahinda.
His reign was notable for the arrival of Buddhism in Sri Lanka under the aegis of the Mauryan Emperor Ashoka. The primary source for his reign is the Mahavamsa, which in turn is based on the more ancient Dipavamsa.
Mahavansa/Chapter 11 tells that ...The king Mutasiva reigned Sixty years in Anuradhapura in Lanka. He had ten sons and two daughters The second son, known by the name Devanampiya Tissa, was foremost among all his brothers in virtue and intelligence. This Devanampiya Tissa became king after his father's death. Even at the time of his consecration many wonders came to pass. In the whole isle of Lanka treasures and jewels that had been buried deep rose up to the surface of the earth. ....King Devanampiya Tissa thought to send pearls to his friend King Dhammasoka. The king sent four persons appointed as his envoys: his nephew Maharittha, who was the chief of his ministers, then his chaplain, a minister and his treasurer, attended by a body of retainers, and he bade them take with them those priceless jewels, the three kinds of precious stones, and the three stems (like) waggon-poles, and a spiral shell winding to the right, and the eight kinds of pearls. When they had embarked at Jambukola and in seven days had reached the haven in safety, and from thence in seven days more had come to Pataliputta, they gave those gifts into the hands of king Dhammasoka. ....When the ministers had stayed five months, highly honoured they set forth with the envoys, on the first day of the bright half of the month Vesakha. Having embarked at Tamalitti and landed at Jambukola they sought out the king, when they arrived here on the twelfth day. The envoys handed the gifts (in return from Dhammasoka) to the ruler of Lanka; the ruler of Lanka made them welcome with great hospitality.
The Mahavamsa mentions an early friendship with Ashoka.... that "the two monarchs, Devanampiyatissa and Dhammasoka, already had been friends a long time, though they had never seen each other", Dhammasoka being an alternate name for Ashoka. The chronicle also mentions Tissa sending gifts to the mighty emperor of the Maurya; in reply Ashoka sent not only gifts but also the news that he had converted to Buddhism, and a plea to Tissa to adopt the faith as well. The king does not appear to have done this at the time, instead adopting the name Devānaṃpiya "Beloved of the Gods" and having himself consecrated King of Lanka in a lavish celebration.
Conversion to Buddhism
Emperor Ashoka took a keen interest in the propagation of Buddhism across the known world, and it was decided that his son, Mahinda, would travel to Sri Lanka and attempt to convert the people there. The events surrounding Mahinda's arrival and meeting with the king form one of the most important legends of Sri Lankan history.
According to the Mahavamsa king Devanampiyatissa was out enjoying a hunt with some 40,000 of his soldiers near a mountain called Mihintale. The date for this is traditionally associated with the full moon day of the month of Poson.
Having come to the foot of Missaka, Devanampiyatissa chased a stag into the thicket, and came across Mahinda (referred to with the honorific title Thera); the Mahavamsa has the great king 'terrified' and convinced that the Thera was in fact a 'yakka', or demon. However, Thera Mahinda declared that 'Recluses we are, O great King, disciples of the King of Dhamma (Buddha) Out of compassion for you alone have we come here from Jambudipa'. Devanampiyatissa recalled the news from his friend Ashoka and realised that these are missionaries sent from India. Thera Mahinda went on to preach to the king's company and preside over the king's conversion to Buddhism.
- See, e.g., Keown, Hodge & Tinti (2003), p. 72, entry for 'Devānampiya Tissa,' where it is translated as 'dear to the gods'.