A king, ancestor of the Sākyas and the Kolians.

In the Ambaṭṭha Sutta DN.i.92 it is stated that Okkāka, being fond of his queen and wishing to transfer the kingdom to her son, banished from the kingdom the elder princes by another wife. These princes were named Okkāmukha, Karakaṇḍa, Hatthinika, and Sīnipura. They lived on the slopes of the Himalaya and, consorting with their sisters and their descendants, formed the Sākyan race.

Okkāka had a slave-girl called Disā, who gave birth to a black baby named, accordingly, Kaṇha. He was the ancestor of the Kaṇhāyanas, of which race the Ambaṭṭha-clan was an offshoot. Later, Kaṇha became a mighty sage and, by his magic power, won in marriage Maddarūpi, another daughter of Okkāka. DN.i.93 DN.i.96

According to the Brāhmaṇa-Dhammika Sutta, Snp.p.52ff. it was during the time of Okkāka that the brahmins started their practice of slaughtering animals for sacrifice. Till then there had been only three diseases in the world—desire, hunger and old age; but from this time onwards the enraged devas afflicted humans with various kinds of suffering.