Harbor Defenses of Manila and Subic Bays

The Harbor Defenses of Manila and Subic Bays ("Coast Defenses of Manila and Subic Bays" until 1925) were a Harbor Defense Command, part of the Philippine Department of the United States Army from circa 1910 through early World War II.

The Board of Fortifications chaired by William H. Taft recommended that key harbors of territories acquired after the Spanish–American War be fortified. Accordingly, El Fraile, Carabao, Corregidor, Grande, and Caballo Islands in the Philippines were to be fortified and incorporated into the harbor defenses of Manila and Subic Bays, protecting the bases of the US Asiatic Fleet and the Philippines Territory's capital and chief port of Manila. From 1922 parts of the defenses were garrisoned by units of the Philippine Scouts, units primarily composed of Filipino enlisted men and US officers.

In July 1941 these units were commanded by Major General George F. Moore, whose Philippine Coast Artillery Command was headquartered at Fort Mills, on Corregidor. This command included Fort Hughes (Caballo Island), Fort Drum (El Fraile Island), and Fort Frank (Carabao Island) at the entrance to Manila Bay, as well as Fort Wint (Grande Island) at the entrance to Subic Bay. At this time there were 4,967 troops assigned to the Harbor Defenses.

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