With all the hundreds of islands and the numerous mixed and indigenous people in the Philippine and Sulu archipelagoes, the whole question, political, commercial, geographical, and strategical, may be simplified by regarding the Philippines as divided into three groups or districts, and the Sulu archipelago as constituting a fourth. These four groups are, roughly:—
- Luzon and Mindoro Islands, in the North, with an area equal to Ohio, and a population of 3,500,000.
- The Bisayan district, between Luzon and Mindanao, a belt of islands from Palauan on the West to Samar on the East, inclusive, and also Calamian, Panay, Negros, Cebu, Bohol, Masbate, and Leyte with an area equal to Kentucky and a population of 2,500,000.
- The Island of Mindanao with an area equal to Indiana and a population of 500,000.
- The Sulu archipelago with an area less than Rhode Island and a population of 100,000.