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).
Spanish language in the Philippines
In Manila, the Spanish language had been more or less widespread, to the point where it has been estimated at around 50% of the population knew Spanish in the late 19th century. In his 1898 book "Yesterdays in the Philippines", covering a period beginning in 1893, the American Joseph Earle Stevens, an American who resided in Manila from 1893 to 1894, wrote:
Long contact between Spanish and the local languages, Chinese dialects, and later Japanese produced a series of pidgins, known as Bamboo Spanish, and the Spanish-based creole Chavacano. At one point these were the language of a substantial proportion of the Philippine population. Unsurprisingly, given that the Philippines was administrated for centuries from New Spain in present-day Mexico, Philippine Spanish is broadly similar to American Spanish, not only in vocabulary, but in pronunciation and grammar.