According to Mahawansa, the king Kashyapa who reigned for 18 years (also known as Sigiri Kashayapa, Kasup, or Kassapa) built his palace on the summit of the Sigiriya rock. Following is the life story of the master artist who created this rock fortress...
Mighty king Dhathusena (also known as Dasenkeliya) who reigned from (459–477 AD) had two sons named Kashayapa and Moggalana (also known as Mugalan), and a daughter who was so dear to him. Mahawansa reveals that the mother of Kashayapa was from an inferior bloodline to the king. But Moggalana's mother was from a bloodline that of equal level to the king. We can speculate that the two brothers having disagreements on the successor of the throne because the Moggalana was senior in bloodline and Kashayapa being the elder son. The throne was normally passed to the eldest son, but in this case Kashayapa had a young competitor from a superior bloodline. This rivalry would have been a popular secret and a possible worry for the king as well. It could also be speculated that the king was secretly thinking of a way to end the rivalry and make peace between the brothers, for the sake of the land and its people.
Possibly, as a step towards avoiding future conflict, King Dhathusena married his beloved daughter to his nephew and made this nephew the chief of army (General - 'Mahasenevi'). What the king did not know was his nephew who is entrusted with the life of his daughter and the kingdom, was indeed a wicked man, who took pleasure in beating up his wife. The poor princess was beaten or even whipped by her husband. With the pure intention to be a good wife, she kept it all a secret, until one day king himself saw her vestments trickling with blood following a beating from her husband. The King was furious and he ordered the nephew's mother to be brunet naked as the punishment for the crimes of her son. It is not clear, and there is no mentioning as to why the king ordered such a punishment. Usually, the wrongdoer is punished by the king's law. But in this case the mother of the offender was punished. Details as to why such a verdict was passed is not mentioned in the Mahawansa or any other history record I could find. It could be speculated that the loving mother of the General placed herself at the wrath of the king by confessing that she was the one who beat the princess taking the blame for his son's crimes. This speculation could be strengthened by the fact, that there is no record of the nephew being stripped off his rank following the verdict.
The wicked General who held the grudge against his king, conspired to dethrone and kill the king. It is obvious, that he used the rivalry between the two brothers Kashyapa and Moggalana to in setting his plan for revenge in motion. The wicked General managed to tempt Kashyapa to seize the throne from his father. It is believed the Moggalana was a mighty warrior, but Kashayapa was a strategist and had a keen eye for details, which allowed him to manage this feat against his father who himself was a mighty warrior. With insufficient forces to challenge Kashyapa's army, Moggalana fled to India with the intention of gathering enough forces to challenge his brother.
King Dhathusena was imprisoned by Kashyapa. The wicked General's plan was working, but he could have no rest until he avenged his mother. Dethroning and imprisonment of his king was not enough for him. He wanted the King Dhathusena murdered. But he had no power over the former king's life. Such an order could only be issued by a another king himself. So he wanted to persuade the new King, Kashayapa to issue such an order. But the General knew that Kashyapa will never issue such an order unless the new king is pushed to the extremes and made to do so. So he embarked on the second stage of his wicked plan by telling the new King, Kashyapa that the former King Dhathusena has hidden his treasure and preserving it for his favourite son, Moggalana. In my personal opinion, Kashayapa would have felt the insecurity of his mother's inferior bloodline and favourations towards Moggalana by everyone, including his father, throughout his life. So, Kashyapa would have been angered not because of the need for treasure, but because he must have felt that he was rejected and will always be a lesser in his father's eyes. It could be this background which made it easier for the wicked General to convince Kashyapa that his father is in fact hiding treasure and waiting for Moggalana to return with the forces. Fallen to the elaborate trap set by the wicked General, Kashyapa sent messengers to his father asking to return the hidden treasure to him. The former king Dhathusena who already had a good hunch on the wicked General's plan, remained silent. Kashyapa repeatedly sent messengers, feeling more and more rejected by the silence of his father. It could be speculated that the King's mind was poisoned further by the wicked General during this time.
With the looming threat of Kashyapa's wrath, and an attempt to reveal the truth to his son, former king Dhathusena agrees to show the place where the treasure is hidden if he was taken to the Kalavapi. Kalavapi is a reservoir tank which is also known as the Kala Weva, built with the sponsorship of King Dhathusena himself. It would obviously have been one of his favorite creations. Upon bathing in Kalavapi, former king Dhathusena took a handful of water and showed the king's messengers and said: "O, friends, this is all the treasure that I possess!". The message which could have been intended to reveal the truth, that Kashyapa already had the prime creation, hence the treasure of former king Dhathusena was brought to the King Kashyapa as an elaborate act of humiliation and an ultimate rejection of him. With this, the wicked General got his opportunity and obtained the permission from King Kashyapa to kill the former king Dhathusena. According to Mahavansa, the wicked General tortured the former king, stripped him naked, bound him with chains inside the wall of his prison with his face to the east, and caused it to be plastered up with clay. Mahavansa also reveals that this was the destiny of king Dhathusena, as karma caught up to him. During the construction of the banks of Kalavapi, king Dhathusena came across a priest meditating in a trance, whom he could not rouse to continue the work. It was said that the king Dhathusena ordered the priest to be covered over with earth (effectively burring the priest alive) and continue the work on the reservoir.
It is obvious that, with time Kashyapa realized the truth in the death of his father in silence (with no reference to a hidden treasure) and the truth in his father's words, (reservoir was the main source of water for the surrounding farmlands which produced food for the whole city). The realization that he ordered the slaying of an innocent and beloved man would have been devastating to Kashayapa who had the sensitive mind of an artist. To this day, underneath the luster of Sigiriya, I feel a certain sadness and regret lingering about everywhere. I'm not sure whether it was my mind playing ticks on me, but it is my personal opinion that Kashayapa regretted his actions throughout his life, and wanted to escape from the past by amercing himself in art and craft.