Since 2002, the Armed Forces of the Philippines, together with the U.S. Special Forces, have been battling with ISIS in what is known as the biggest battle of the country against the radical Islamic terrorists since WWII. The Philippines was once a colony of Spain that spread Catholicism all over the country, making it a predominantly Christian nation. However, the country’s southern islands are home to a large Muslim population wherein there has been some form of push, political or terrorist, to create an independent Muslim state.
Source: https://www.wearethemighty.com/intel/biggest-battle-in-philippines-since-wwii/
