Spanish–Moro conflict
The Spanish initiated the conflict by conquering the Philippines and invading Moro territory in an effort to subjugate the region to their rule since the 1500s. When the Spanish conquered the Muslim Kingdom of Maynila, a vassal of the Sultanate of Brunei, the Islamic rajah, Rajah Sulayman resisted the Spanish. Manila then became the capital of the Spanish Philippines after the conquest, with the Spanish forcibly converting people to Catholicism. The Spanish–Moro Wars started with the Castille War, a war between Spaniards and the Sultanate of Brunei. (The term "Moro" at this time included Muslim Tagalogs who were ruled by the Sultanate of Brunei).
Cordillera Central (Luzon)
The Philippines, named after King Philip II of Spain in 1618, was already of interest to Spain before the Spaniards even reached the land. In 1565, reports of huge gold mines in the Cordillera reached the Viceroy of Mexico, which led to the first official Spanish expedition to the Cordillera in 1576. King Philip III, waging the Thirty Year War which needed funding, sent orders for large expeditions to the Philippines.
In 1620, Captain Garcia de Aldana Cabrera offered the resisting Igorot tribal leaders clemency if they were willing to accept Catholic religion, obey the Spanish government and pay a fifth of all their mined gold to the Spanish King. They refused and the Spanish conquerors built forts and organized military troops to start the exploitation of the gold mines.