The Sultanate of Maguindanao (Maguindanaon: Kasultanan nu Magindanaw, كاسولتانن نو ماڬينداناو; Jawi: کسلطانن ماڬيندناو; Iranun: Kesultanan a Magindanao; ; ) was a sultanate that ruled parts of the island of Mindanao, in the southern Philippines, especially in modern-day Maguindanao provinces (Maguindanao del Sur and Maguindanao del Norte), Soccsksargen, Zamboanga Peninsula and Davao Region. Its known historical influence stretches from the peninsula of Zamboanga to the bay of Sarangani. During the era of European colonization, the Sultanate maintained friendly relations with British and Dutch traders. History Before the founding of the Sultanate of Maguindanao, according to the Yuan Dynasty annals, Nanhai Zhi (At year 1304), a polity known as Wenduling 文杜陵 was its predecessor-state. This Wenduling was invaded by then Hindu Brunei, called Pon-i (present-day Sultanate of Brunei), until it rebelled against Pon-i after the Majapahit Empire's invasion of Pon-i. Islamization then happened afterwards. Firstly, two brothers named Mamalu and Tabunaway lived peacefully in the Cotabato Valley on Mindanao and then Shariff Mohammed Kabungsuwan of Johor in what is now modern day Malaysia, preached Islam in the area in the 16th century, Tabunaway converted, while Mamalu decided to hold fast to their ancestral animist beliefs. The brothers parted ways, with Tabunaway heading to the lowlands and Mamalu to the mountains, but they vowed to honor their kinship, and thus an unwritten pact of peace between Maguindanaons and the indigenous peoples was forged through the two brothers. As Shariff Kabungsuwan introduced Islam in the area, which was earlier Hindu-influenced from Srivijaya times, at the end of the 16th century and established himself as Sultan seated in Malabang-Lanao. He exiled some of his people who apostatised to Cotabato. He subsequently married into the families of local chieftains and established the Sultanate of Maguindanao, with its seat in Slangan (the western part of present-day Cotabato), making him virtually Sultan of the whole island. The sultanate was usually centered in the Cotabato Valley. Asraf Mohamad Samalan Dipatuan Qudratullah Fahar'uddin Nasiruddin, popularly known as Kudarat and whose name as a youth was Ullah Untong, was one of the greatest sultans who controlled Mindanao. In his island sanctuary in Sulu, he was known as Sultan Nasiruddin and after his reign was buried there. His grandson Abd al-Rahman continued increasing the Sultanate's power and influence. The Maguindanao Sultanate also had a close alliance with the Ternate Sultanate, a sultanate in the Moluccas region of Indonesia. Ternate regularly sent