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).
Filipinos in the French military
In 1858, when the Philippines was a Spanish colony, France and Spain invaded Vietnam. A number of French troops involved in this campaign became casualties as a result of contracting illnesses such as cholera, dysentery, tropical diseases, and rickets. In order to deal with the manpower shortage which resulted from this situation, the French consul in Manila, the colonial capital of the Philippines, was given permission by the Spanish government to recruit nine hundred Indians, as Filipinos were then known, for the French navy and a sufficient number of men to form an infantry company and a cavalry squadron. It is said that one-third of the entire French force in this campaign consisted of mercenaries from the Philippines, who distinguished themselves in action and were well adapted to the environment.