The Zamboanga Peninsula (geographic landform) is a long, semicircular peninsula and the northwestern part of Mindanao Island, the southern part of the Philippines. It is located primarily within the Zamboanga Peninsula (Region IX).
The peninsula is connected to the main section of Mindanao Island through an isthmus situated between Panguil Bay and Pagadian Bay.
Zamboanga Peninsula extends southwesterly toward the Sulu Archipelago and Borneo island. It has an area of roughly 5,600 square miles (14,500 square km). It is between the Sulu Sea on the north and west, and the Moro Gulf of the Celebes Sea on the south.
The boundary between the peninsula and the mainland is politically defined by the border between the peninsula's Zamboanga del Sur province and main island's Lanao del Norte province. The geographic Zamboanga Peninsula consists of the provinces of Zamboanga del Norte, Zamboanga del Sur, Zamboanga Sibugay of Zamboanga Peninsula (Region IX); and the northwestern province of Misamis Occidental in the Northern Mindanao (Region X), and the independent Zamboanga City.
The land of almost 4 million people belonging to the people of Mindanao, the Lumad groups who are pagans, the converted Moro groups, the converted Christian groups and the Christians and non-Christian settlers. the region is believed to be first inhabited by Subanon, which is considered as the largest Lumad ethnic group in Mindanao. During the Islamic colonization, some Subanon converted to Islam and accepted the Islamic culture whom we call today the Kalibogan and those Subanon who accepted the Christian faith, Hispanic Culture and names are today's Zamboangueño.