In the early years Siddhartha was pampered with all the worldly pleasures and cautiously kept away from the pain and sufferings. It was done because of a prophecy, which said that Gautama would renounce his kingdom to become an ascetic. Due to such a prophecy made by sage Asita from an early childhood Siddhartha was pampered with all kinds of worldly pleasures.
The first description of Kanthaka is available in the event revolving around Siddhartha and Yasodhara's marriage. According to the Sakyan customs to prove his capability a prince was needed to show his expertise in archery, horse riding and swordplay. Contests were held where the worthiest prince would become the groom. Siddhartha defeated his cousin Devadatta in archery, Aniruddha in horse riding and Nanda in swordplay. The prince competed in all these sports while mounted on Kanthaka. Later when the prince fled the palace to become an ascetic he rode on this horse. Channa, the head royal servant, saddled Kanthaka and guided him out of the town by the bank of Anoma River.
There are several stories that are associated with the death of Kanthaka. But it is widely believed that the horse died, as it could not bear the sorrow of staying away from the prince. According to Buddhist texts Kanthaka was reborn as a Brahmin. The figure of Kanthana, the white horse, can be found on the carvings of the Buddhist stupas.