The Battle of Manila Bay took place on 1 May 1898, during the Spanish-American War. The American Asiatic Squadron under Commodore George Dewey engaged the Spanish Pacific Squadron under Admiral Patricio Montojo y Pasarón and destroyed the Spanish squadron. The engagement took place in Manila Bay, the Philippines, and was the first major engagement of the Spanish-American War.
At daybreak on 1 May, George Dewey aboard the protected cruiser USS Olympia led a small squadron of ships into Manila Bay. Two mines were exploded but were ineffective. At 5:10 a.m., the Spaniards opened fire. At 5:40 with the now famous phrase, "You may fire when ready, Gridley," the Olympia's captain was instructed to begin the barrage that resulted in the destruction of the Spanish flotilla.
The U.S. squadron swung in front of the Spanish ships and forts in single file, firing their port guns. They then passed back, firing their starboard guns. This was repeated five times, each time at closer range. Most of the Spanish ships were either destroyed or surrendered. The Spanish fleet fought back with ferocity, but many crews were caught unaware—painting their vessels, or at Mass. The eleven Spanish ships and five land batteries fought back for two and a half hours. The American ships withdrew at 7:45 a.m., then attacked again at 10:40. The Spanish colors were struck in surrender at 12:40 p.m. The results were decisive; Dewey won the battle with only a single fatality among his crew, Francis B. Randall, Chief Engineer on the McCulloch from heart attack.