either of two distinct but remotely related Indian dynasties. The Western Gaṅgas ruled in Mysore state (Gaṅgavāḍi) from about AD 250 to about 1004. The Eastern Gaṅgas ruled Kaliṅga from 1028 to 1434–35.

The first ruler of the Western Gaṅga, Koṅgaṇivarman, carved out a kingdom by conquest, but his successors, Mādhava I and Harivarman, expanded their influence by marital and military alliances with the Pallavas, Cālukyas, and Kadambas. By the end of the 8th century a dynastic dispute weakened the Gaṅgas, but Būṭuga II (c. 937–960) obtained extensive territories between the Tungabhadra and the Krishna rivers, ruling from Talakād (the capital) to Vātāpi. Repeated Cōḷa (Chola dynasty) invasions cut the contact between Gaṅgavāḍi and the imperial capital, and Talakād fell into the hands of the Cōḷa ruler Viṣṇuvardhana in about 1004. Most of the Western Gaṅgas were Jainas, but some patronized Brahmanical Hinduism. They encouraged scholarly work in Kannada (Kanarese), built some remarkable temples, and encouraged deforestation, irrigation, and cross-peninsular trade.

The Eastern Gaṅgas arose to intermarry with and challenge the Cōḷas and Cālukyas in the period when the Western Gaṅgas had been forced to abandon this role. Early dynasties of the eastern Gaṅgas ruled in Orissa from the 8th century; but Vajrahasta III, who assumed the title of Trikaliṅgādhipat (ruler of the three Kaliṅgas) in 1028, was probably the first to rule all three divisions of Kaliṅga. His son Rājarāja I waged war upon the Cōḷas and the Eastern Cālukyas and strengthened the dynasty by marrying a Cōḷa princess, Rājasundarī. Their son, Anantavarman Cōḍagaṅgadeva, ruled from the mouth of the Ganges River in the north to the mouth of the Godāvari River in the south; he began building the great Jagannātha temple at Purī at the end of the 11th century. Rājarāja III ascended the throne in 1198 and did nothing to resist the Muslims of Bengal, who invaded Orissa in 1206. Rājarāja's son Anaṅgabhīma III, however, repulsed the Muslims and built the temple of Megheśvara at Bhuvaneśvara. Narasiṃha I, the son of Anaṅgabhīma, invaded southern Bengal in 1243, defeated its Muslim ruler, captured the capital (Gauḍa), and built the Sun Temple at Konārak to commemorate his victory. With the death of Narasiṃha in 1264, the Eastern Gaṅgas began to decline; the sultan of Delhi invaded Orissa in 1324, Muslims raided in 1353, and Vijayanagar defeated the Orissan powers in 1356. Narasiṃha IV, the last known king of the Eastern Gaṅga dynasty, ruled until 1425. The “mad king,” Bhānudeva IV, who succeeded him, left no inscriptions; his minister Kapilendra usurped the throne and founded the Sūryavaṃśa dynasty in 1434–35. The Eastern Gaṅgas were great patrons of religion and the arts, and the temples of the Gaṅga period rank among the masterpieces of Hindu architecture.