The Battle of Mactan was fought on a beach in Mactan Island between Spanish forces led by the Portuguese explorer Ferdinand Magellan along with local allies, and Lapulapu, the chieftain of the island, on the early morning hours of April 27, 1521. Magellan, a Portuguese-born commander serving the Spanish Empire who led an expedition that ultimately circumnavigated the world for the first time, commanded a small Spanish contingent in an effort to subdue Mactan led by Lapulapu under the Spanish crown. The sheer number of Lapulapu's forces, compounded with issues on the location and armor, ultimately resulted in a disastrous defeat to the Europeans and the death of Magellan. Surviving members of Magellan's crew continued the expedition under the command of Juan Sebastian de Elcano, who completed the journey in September 1522.

Mactan is a densely populated island located a few kilometers east of Cebu Island in the Philippines. The island is part of Cebu province and it is divided into the city of Lapu-Lapu and the municipality of Cordova. The island is separated from Cebu by the Mactan Channel which is presently crossed by three bridges: the Cebu–Cordova Link Expressway (CCLEX), the Mactan–Mandaue Bridge, and the Marcelo Fernan Bridge. The island covers some 65 square kilometres (25 sq mi) and has a population of 527,071 as of 2020, making it the nation's most densely populated island. Along with Olango Island Group, the isles are administered by a city and a municipality covering 75.25 square kilometres (29.05 sq mi).