King of Ceylon (247-207 B.C.). He was the second son of Mutasíva. It is said that on the day of his coronation many wonderful treasures miraculously appeared, some of which he resolved to send as tokens of esteem to his contemporary Dhammásoka of India, with whom he had long been on terms of friendship. An embassy, led by his nephew Mahárittha, was despatched to Pátaliputta, and the emperor showed the ambassadors every mark of honour. He sent back with them all the requisites for a coronation, with instructions to celebrate the inauguration of the Sinhalese king, whom he invited to embrace Buddhism. On the return of the embassy, the king was solemnly crowned a second time. This confirmation of Devánampiyatissa's sovereignty under the aegis of Asoka may have been due either to the commanding position of Asoka or for the strengthening of family connections. Asoka was a Moriyan (a branch of the Sákiyans) and Devánampiyatissa had Sákiyan blood.
The chief event in the reign of Devánampiyatissa was the arrival of Mahinda in Ceylon. He arrived at the head of a mission in the year of the king's second coronation. Mahinda met the king hunting on the full-moon day of Jettha. The king welcomed him with great honour and speedily embraced the new religion, to which Asoka had already drawn his attention.
His conversion was the direct result of Mahinda's preaching of the Cúlahatthipadopama Sutta. His earlier religion is not known, it may have been Jainism. His example was followed by a large number of his subjects, many of whom entered the Order. Devánampiyatissa dedicated to their use the Nandana park and the Mahámeghavana, which he himself had laid out a little earlier. In the Mahámeghavana he built the famous Mahá-Vihára which, for many centuries, remained the centre of the orthodox religion in Ceylon. The dedication of the Mahá-Vihára took place in the two hundred and thirty-sixth year after the death of the Buddha. The king's next pious work was the erection of the Cetiyapabbata-vihára and he, later, built the Thúpáráma, containing the Buddha's right collar-bone.
When the women of the palace, led by Anulá, wife of the sub-king, Mahánága, expressed a desire to become nuns, Devánampiyatissa sent another embassy to Asoka asking him to send Sanghamittá, together with the right branch of the sacred Bodhi-tree. This branch miraculously severed itself from the parent tree and, together with Sanghamittá, was conveyed down the Ganges and arrived in Jambukola, where it was received with all honour by Devánampiyatissa. From Jambukola it was taken in procession to Anurádhapura, where it was planted in the Mahámeghavana, the king instituting in its honour a festival, which was observed for many centuries. For the use of Sanghamittá and the nuns the king erected various buildings, the chief of which was the Hatthálhaka-vihára and the Upásiká-vihára with its twelve mansions. (This account is summarised from the Mahávamsa (chaps.xi., xiii.-xx.); also Dpv.xi.14ff; xii.7; xvii.92).
Among other works of Devánampiyatissa we are told of the building of the Issarasamana- and the Vessagiri-viháras, the refectory called Mahápáli, the Jambukola-vihára in Nágadípa, the Tissamahá-vihára, the Pácínáráma and the Pathamathúpa. He also built the Tissavápi at Anurádhapura. (The Cv. (xxxvii.94) mentions also the Dhammacakka as having been built by Devánampiyatissa. It later became the Temple of the Tooth at Anurádhapura).
Mahinda survived him by eight years. Devánampiyatissa seems to have died without issue, for he was succeeded by four of his brothers.