With losses to the Spanish navy increasing, and the eventual fall in profits from slave selling, raiding became less appealing to the Iranuns and their Islamic supporters. Uneconomical patriotism simply did not make quite an appeal. Thus, it came to pass that the Moro pirates faded from Mindoro's history. The pirate fort in Mamburao was abandoned, and the Moros retreated to Mindanao to consolidate their forces and continue the Moslem resistance at the homefront. Mindoro Island then became a Spanish possession in a truer sense for the first time. But not for long.