On May 23, 1578, Governor Francisco de Sande, who had taken possession of Borneo for Spain, sent off an officer, Esteban Rodriguez de Figueroa, to subdue the Sulu Islands, instructing him to convert (as gently as he can) the pirates of that place into peaceful farmers, paying tribute to the Spanish Crown.
De Sande was the third governor of the Philippines who ruled from August 25, 1575 to April 1580. Part of his order to Rodriguez de Figueroa and notarized by Alonso Betran, reads:
That which you, Captain Esteban Rodriguez de Figueroa shall observe on the expedition which you are about to make, God our Lord helping, is as follows: From this city and island of Borney (Borneo), God willing, you shall go to the islands of Xolo (Sulu), where you shall endeavor to reduce that chief and his people to the obedience of his Majesty. You shall bargain with them as to what tribute they shall pay, which shall be in pearls, as they are wont to give to the king of Borney.
After having finished affairs in Xolo, if time permits you shall, God willing, go to the island of Mindanao. There you shall try, by the most convenient methods and with friendliness, to reduce the chief of the river of Mindanao, and the other chief of that island, and those nearby, to the obedience of his Majesty—giving him to understand what they will gain in becoming his Majesty’s vassals and our allies, and in having trade with us.
You shall also tell them that the gain affects them chiefly, since we come to teach them our civilization, and most of all the service of God, our Lord, who created and redeemed them, and of whom they are ignorant; and how to live in accord with natural law, as is their obligation.
You shall order them not to admit any more preachers of the doctrine of Mahoma (Mohammed), since it is evil and false, and that of the Christians alone is good. And because we have been in these regions so short a time, the lord of Mindanao has been deceived by the preachers of Borney, and the people become Moros.