Kanthaka (in Pali and Sanskrit) (6th century BC, in Kapilvastu and Tilaurakot, Nepal) was a favourite white horse of length eighteen cubits that was a royal servant of Prince Siddhartha, who later became Gautama Buddha. Siddhartha used Kanthaka in all major events described in Buddhist texts prior to his renunciation of the world. Following the departure of Siddhartha, Kanthaka died of a broken heart.
In the court of King Suddhodarna, Kanthaka was the most skillful and able horse, and the favourite of Crown Prince Siddhartha, whenever Siddhartha needed to go outside the palace. Siddhartha had been lavished and pampered in a series of purpose-built palaces by Suddhodarna in order to shield him from thoughts of pain and suffering. This was done due to a prophecy by the ascetic Asita, who predicted that Siddhartha would renounce the throne to become a spiritual leader were he to contemplate human suffering. Kanthaka is first described in relation to the events leading up to the marriage of Siddhartha to Yasodhara, another Sakyan princess. By the customs of the kshatriya Sakyan clan, a prince must prove his worthiness in warrior related skills such as horse-riding, mounted archery and swordplay by defeating other royals in such contests. Mounted on Kanthaka, Siddhartha defeated his cousin Devadatta in archery, another cousin Anuruddha in a horse-riding competition and then half-brother Nanda in swordplay.
After Siddhartha's marriage, Kanthaka was the horse pulling the chariot when Channa, the head royal servant accompanied Siddhartha around Kapilavastu to see the Four sights whilst meeting his subjects, which prompted his decision to renounce the world. During these expeditions aboard Kanthaka, Channa explained to Siddhartha the sights of an elderly man, a sick person, a dead person whose funeral was being conducted and finally, an ascetic who had renounced worldly life for a spiritual one, as Siddhartha who had been secluded from such sights within the palace was taken aback.