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).
Iloilo City
In 1566, as the Spanish conquest of the Philippines was underway and moving north toward Manila, the Spaniards launched several expeditions from Mexico and under Miguel López de Legazpi, came to Panay and established a settlement in Ogtong (Oton).
Unlike the Indianized Cebuanos who were neutral to the Spaniards or the partially islamized Tagalogs of Manila who were more hostile, the people of Madja-as welcomed the Iberians as allies since at that time period, Madya-as was locked in a war against the invading Muslims, especially with the Sultanate of Brunei and its vassal states, the Sultanate of Sulu and the Kingdom of Maynila which, according to Spanish Governor-General Franciso de Sande, are their blood-cousins. The people then fervently accepted Christianity as they supplied the bulk of the mercenaries used in the conquest of partially islamized Manila, whose rulers were related to the Sultan of Brunei.