The founding independent ruler of the Passara kingdom is Upasona’s son Sumila.

Upasona, who was the general of King Jayasena, helped King Satha of Badulla to conquer Passara, and Satha gave his daughter to Upasona.

Upasona got a son named Sumila from that queen. After the death of Jayasena, his son Satha I was consecrated in the kingdom of Badulla.

Sata II gave his sister’s son Sumila the vassal power of the kingdom of Passara.

Sumila, who was in power in the kingdom of Passara, secretly organized the army, conquered Hewaheta kingdom, Rangiri Dambulla, Dimbulagala kingdom and Mahiyangana kingdom.

Then Sumila sent a message to the king that he was no longer a feudal king of Badulla. On hearing the success of his sister’s son, King Satha freed him from feudality and sent a reply.

But Sumila, who was not satisfied with that, sent a letter informing him that he would appoint King Satha as his general.

Reading the letter, king Satha, who was furious, left for Pasara to fight with Sumila. But Satha was defeated in that battle and returned to his kingdom as a Passara vassal.

At the same time, Sumila ordered King Bimbisara I of Monaragala Kingdom to surrender. King Bimbisara’s chief generals were sent to battle, and Bimsara was defeated and a peace treaty was reached.

King Bimsara’s daughter Sundari was married to Sumila. But before long, King Suba, who was invading Dighavapiya, defeated King Bimbisara and conquered the kingdom of Monaragala. By this time, the kingdom of Hewahata had been freed from Sumila and ruled by the son of king Suba named Aggimitta.

Excited by this, Aggimitta went to Passara and fought with Sumila, but after losing his army, he retreated to Monaragala.

In the meantime, king Suba liberated and conquered the Malla Kingdom of Ratnapura from Sumila. Then Mahiangana was also acquired. Then he conquered Bandarawela in the same way. King Suba sent letters that all Monaragala feudal colonies belonged to him again. They also warned that if they did not surrender, king Suba would come and conquer them.

Sumila, who sent a reply, mentioned that Bimbisara’s daughter was his queen and therefore Monaragala belonged to him legally and that he would kill King Suba in Monaragala and build an empire again.

After that Sumila who went to Madugoda was defeated by Aggimitta and retreated to Hasalaka and stayed there. King Suba left Monaragala to launch an attack on Hasalaka, but on the way he heard that King Satha kanha was coming there to conquer Monaragala and retreated back to Monaragala itself.

Sumila, who spent the rest of his life in the kingdom of Hasalaka, handed over the kingdom to his son Sala and died after reigning for twenty-seven years.