Background
He was a direct descendant of Shariff Kabungsuwan, a Muslim missionary who preached Islam in the Philippines and established the sultanate after marrying a Sulu princess in the 16th century.
He was a direct descendant of Shariff Kabungsuwan, a Muslim missionary who preached Islam in the Philippines and established the sultanate after marrying a Sulu princess in the 16th century.
Buisan was the younger half-brother of Sultan Dimasangcay Adel (reigned: 1578–1585) and Sultan Gugu Sarikula (reigned: 1585–1597), both having ties with the Sultanate of Sulu. The Rajah Muda was Dimasangcay"s son. In 1597, Buisan lost at the Battle of Buayan.
So, later, in 1602, he joined forces with Rajah Sirongan to raid Spanish settlements at Cuyo and Calamianes islands with 100 boats that could accommodate over 100 men each.
However, after an unsuccessful raid (pangangayaw as it was locally known) in 1606, Buisan distanced himself and the Rajah Muda away from Sirongan and established a new community by the Cotabato coast. Earlier, on September 8, 1605, Sirongan had already signed a treaty with the Spanish, swearing allegiance to the King of Spain.
The Spanish recognized that Sirongan had real power over Maguindanao and not Buisan. Sirongan then helped the Spanish in fighting the Portuguese in Malacca.
Soon enough, Sirongan"s power waned.