The Moro Peoples
In 1899 the US Army estimated there were somewhere between 350 to 500,000 Muslims, 150 to 200,000 pagan tribesmen, and 50-60,000 Christian Filipinos (most Visayan) living in Mindanao, Sulu, and southern Palawan. No estimate was made, but there were likely 10-15,000 ethnic Chinese, generally concentrated in the port cities of Zamboanga, Jolo, and Cotabato. This was at a time when the U.S. population was approximately 76 million (about one-quarter of today's) and the entire Philippine Islands 6-7 million (today it approaches 90 million). The number of Muslims in the Philippines in 2007 was estimated somewhere between 5-7 million.
Of the 10-12 different Moro peoples, three were dominant in size and power. The Cotabato Basin was the homeland of the Maguindanaos, the "people of the flood plain." It was a vast interior waterway centered on the Cotabato River and its tributaries; known in 1900 by the name given it by the Spanish maps, the "Rio Grande." Fed from large upland lakes by the heavy rainfall of the thickly forested highlands, water dropped to a vast, low swampland of slow, meandering streams, subject to regular flooding as the watercourse met the incoming ocean tides at the river’s wide delta. This was the homeland of the Maguindanaos, “the people of the flood plain.” The name Mindanao came from the Maguindanaos. In 1899, the City of Cotabato, near the mouth of the river, was a Spanish and Christian Filipino outpost. The Magindanaos were subdivided, into three political units, or sultanates: Maguindano in the lower valley, Buayan in the northern upper river valley, and Bagumbayan in between. Farming constituted the core of the economy and rice was the principal crop. With the arrival of the Americans and the entrepreneurship of Datu Piang, the region became known for its gutta percha trees, which produced a rubber-like resin that became widely used to insulate and waterproof undersea cables.
Map of the Cotabato River Basin - Home of the Maguindanaos