The Spanish-held Castillo San Felipe del Morro in San Juan, Puerto Rico having been besieged for fifteen days, surrenders to an English force under Sir George Clifford, Earl of Cumberland.

Castillo San Felipe del Morro, most commonly known as El Morro, is a large fortress and citadel in the Old San Juan historic quarter of San Juan, the capital municipality of Puerto Rico. Commissioned by King Charles I of Spain in 1539, it was first built as a fortified tower in honor of King Philip II, who oversaw its expansion into a hornwork bastion fort by 1595. Over the next 200 years, especially in the reign of King Charles III, El Morro continued to be developed to reach its current form in 1787. Rising 43 metres (140 ft) from the Atlantic shoreline with 5.5 to 7.6 metres thick walls, the six-leveled edifice stands on a steep, rocky headland promontory on San Juan Islet guarding the entry to San Juan Bay, the harbor of Old San Juan. El Morro, alongside La Fortaleza, San Cristóbal, El Cañuelo, and other forts part of the Walls of Old San Juan, protected strategically and militarily important Puerto Rico, or La Llave de las Indias, from invasion by competing world powers during the Age of Discovery and Sail. It was designated a World Heritage Site by UNESCO in 1983.

San Juan is the capital city and most populous municipality in the Commonwealth of Puerto Rico, an unincorporated territory of the United States. As of the 2020 census, it is the 57th-most populous city under the jurisdiction of the United States, with a population of 342,259. San Juan was founded by Spanish colonists in 1521, who called it Ciudad de Puerto Rico.

The Battle of San Juan was a military and naval action on June 15, 1598 when an English force of 20 ships and 1,700 men under Sir George Clifford, Earl of Cumberland, overwhelmed and took the Spanish fortress Castillo San Felipe del Morro and thus took the city of San Juan, Puerto Rico. They were able to hold the castle for 65 days but disease took its toll and the English forces left, but not before sacking and burning San Juan to the ground. This was the only attack that broke through and captured El Morro castle.