Dhatarattha (धतरट्ठ) is the pali variant of sanskrit name Dhritarashtra (धृतराष्ट्र), who is a major deity in Buddhism and one of the Four Heavenly Kings. His name means "Upholder of the Nation." Dhṛtarāṣṭra is the guardian of the eastern direction. He lives on the eastern part of Sumeru. He is leader of the gandharvas and piśācas.
In the Pāli Canon of Theravāda Buddhism, Dhṛtarāṣṭra is called Dhataraṭṭha. Dhataraṭṭha is one of the Cātummahārājāno, or "Four Great Kings." each of whom rules over a specific direction.
He has many sons who go by the title "Indra, as well as a daughter named Sirī. A mythical king, mentioned in a list of kings - with Vessāmitta, Atthaka, Yāmataggi, Usinnara and Sivi - as having entered Sakka's heaven by virtue of his righteousness and his waiting on pious men. J.vi.251.
Although an entirely separate figure, Buddhist literature features a Nāga King also named Dhṛtarāṣṭra. He was the father of Gautama Buddha in a past life when the latter was a bodhisattva named Bhūridatta. His story may be found in the Bhūridatta Jātaka of the Pali Canon.
He is also mentioned in several Mahāyāna Sutras, including the Mahāmāyūrī Vidyārājñī Sūtra and the Mahāmegha Sūtra.
Under the title "Dhatarattha" in 'Buddhist Dictionary of Pali Proper Names' we find following entries:
1. Dhatarattha - One of the Cātummahārājikā, the ruler of the Eastern Quarter. His followers are the Gandhabbas. He has numerous sons called Indra (D.ii.207, 220, 257f; iii.197). He was present at the preaching of the Mahāsamaya Sutta and the ātānātiya Sutta. The name of his daughter is Sirī (J.iii.257).
2. Dhatarattha - A mythical king, mentioned in a list of kings - with Vessāmitta, Atthaka, Yāmataggi, Usinnara and Sivi - as having entered Sakka's heaven by virtue of his righteousness and his waiting on pious men. J.vi.251.
3. Dhatarattha - There were two kings of this name, contemporaries and vassals of Renu. One of these two was king of Angā with his capital in Campā, and the other of the Kāsīs with his capital in Benares. D.ii.235f.
4. Dhatarattha - A Nāga king. Thanks to the scheming of the tortoise Cittacūla, he married Samuddajā, daughter of the king of Benares. They had four sons: Sudassana, Bhūridatta, Subhaga and Kānārittha. His kingdom was beneath the Yamunā. Dhatarattha is identified with Suddhodana. J.vi.162ff., 171.186, 200, 219. For details see the Bhūridatta Jātaka.
5. Dhatarattha - The Bodhisatta born as king of the hamsas. He lived in Cittakūta, at the head of ninety thousand hamsas. One day he was caught in a snare on the lake Khemā, set by the orders of King Bahuputtaka. Dhatarattha's friend, Sumukha, refused to leave him while he was caught. The two friends melted the heart of the hunter when he came to take Dhatarattha, and later they were brought before the king. Dhatarattha preached the Doctrine to the king and to his queen, Khemā, who longed to hear a hamsa preach (J.iv.425ff; for details see the Hamsa Jātaka). Dhatarattha is often referred toe as a king surrounded by a splendid following. E.g., DA.i.40; MA.ii.576; UdA.57, 412; PvA.171.
6. Dhatarattha - The family of hamsas to which belonged Dhatarattha, king of the hamsas. The members of this family are called Dhataratthā. They were golden-coloured and lived in Cittakūta. The Mahā-Sutasoma Jātaka (J.v.345, 355, 357) contains a story of the complete destruction of these hamsas. They lived in Kañcanaguhā, and during the four months of the rainy season would not leave their cave, in case their wings should be drenched with water and they fell into the sea. A spider, as big as a cartwheel, used to weave a thick web at the entrance to the cave, but the Dhatarattha geese sent one of their young ones, who had received two portions of food, to cut through the web. One season, however, the rains lasted for four months, and the hamsas became cannibals and thus lost their strength. When, at the end of the rains, they tried to break through the web, they failed, and the spider cut off their heads one by one and drank their blood. This was the end of the Dhatarattha hamsas. J.v.469f.
7. Dhatarattha - A class of Nāgas (D.ii.259), descendants of the Nāga king Dhatarattha and of Samuddajā (J.vi.219), and possessed great power. They dwell in the Sattasidantara-samuda (SA.ii.254).