In Greek mythology, Hydaspes (Ὑδάσπης), was an Indian river god with an extraordinary swift stream that flows into the Saronitic Syrtis. It is the modern day, Jhelum River in modern Pakistan.
The poet Nonnus in the Dionysiaca, makes the Hydaspes a titan-descended god, the son of the sea-god Thaumas and the cloud-goddess Elektra, an Oceanid. He was the brother of Iris, the goddess of the rainbow. Hydaspes fathered by Astris, daughter of Helios, Deriades the king of India. He supported the Indians in their war against the invading armies of the god Dionysos.
"The whole army was led to battle by the emperor of the [null Indians] [i.e. Deriades], son of Hydaspes the watery lover in union with Astris daughter of Helios, happy in her offspring — men say that her mother was Ceto, a Naiad daughter of Oceanos — and Hydaspes crept into her bower till he flooded it, and wooed her to his embrace with conjugal waves. He had the genuine Titan blood; for from the bed of primeval Thaumas his rosy arm consort Electra brought forth two children — from that bed came a river and a messenger of the heavenly ones, Iris quick as the wind and swiftly flowing Hydaspes, Iris travelling on foot and Hydaspes by water. Both had an equal speed on two contrasted paths: Iris among the immortals and Hydaspes among the rivers."
According to Plutarch, Hydaspes was the father of Chrysippe, who fell in love with her own father.
The goddess Aphrodite was offended by Chrysippe and thus by her impulse, she made the princess fell in love with her own father. The girl not being able to curb her preternatural desires, by the help of her nurse, in the dead of the night got to the king's bed and lay with him. When Hydaspes proving unfortunate in his affairs and realizing what had happened, he crucified his daughter and buried her nurse alive for her betrayal. Soon after that, overcome with grief for the loss of Chrysippe, he threw himself into the river Indus (presumably not the same as the Indian river commonly known as Indus), which was said to have been renamed Hydaspes after him.