The eastern areas of the fort were in the district called Moanalua. It was royal land won by conquest by Kamehameha I in the 1790s and eventually passed to Bernice Pauahi Bishop and then inherited by Samuel Mills Damon in 1884. The western side known as Halawa, was the former beach-front estate of Queen Emma of Hawaii. The sandy dunes had been used as a burial site. It was used for the U.S. Army in 1901, and acquired by the U.S. federal government in 1907 by condemnation from Emma's estate. It was sometimes called "Queen Emma Military Reservation" or "Queen Emma Point". Secretary of WarWilliam Howard Taft under President Theodore Roosevelt headed a group to review coastal defenses, in light of "possessions" such as Hawaii and the Philippines, based on the findings of the Board of Fortifications. Originally named Fort Upton for General Emory Upton, on January 28, 1909 after local citizens objected, Archibald Cleghorn suggested the name be changed to honor Kamehameha I, the first king of the unified Hawaiian islands.
First phase
From east to west the sites built in the first phase were:
Battery Selfridge
Battery Selfridge was constructed from November 1907 to 1913 with two 12-inch M1895 guns on disappearing carriages, with a range of about. It was fort building 420, NRHP site 84000975, located at. It was named for Lt Thomas Etholen Selfridge.
Battery Jackson
Battery Jackson was constructed in 1913 was equipped with two 6-inch guns on disappearing carriages, with a range of about. It was fort building 430, about, state site 80-13-1601 and NRHP site 84000954,. It was named for American Civil War General Richard H. Jackson. A massive concrete air raid shelter was built in 1915.
Battery Hawkins
Battery Hawkins was constructed in 1914 with two 3-inch guns with a range of about. It was fort building 440, NRHP site 84000928 located at, 440 Nelson Avenue. Another bunker built here was known as Hawkins annex, fort building 450, NRHP site 84000948, state site 80-13-1603. Although the smallest of the batteries, it is the easiest to access. It was named for General Hamilton Smith Hawkins.
Battery Hasbrouck
Battery Hasbrouck was constructed from July 1909 to 1914 and was equipped with eight 12-inch coast defense mortars, with a range of about. It was fort building 460 and NRHP site 84000925. It was directly east of the entrance to Pearl Harbor, designed to protect its mine field, at coordinates, covering. It was named for General Henry Cornelius Hasbrouck son of William C. Hasbrouck.
Battery Chandler and Barri
At the west end of Fort Kamehameha, coordinates Battery Chandler had two guns named for Lt. Rex Chandler who died in an airplane crash in 1913. Battery Barri had two 4.7-inch guns, was named for Captain Thomas O. Barri who died in the Civil War in 1863. Construction on these was started in September 1914. Barri was dismantled in 1925 and both no longer exist.
Batteries Adair and Boyd
Each of these had two 6-inch Armstrong guns in casemates located on Ford Island. They were constructed starting in August 1916 and named for Lt Henry R. Adair and Captain Charles T. Boyd. A few years later an airfield called Luke Field was built on Ford Island, and the site is now owned by the Navy.
Battery Closson
The batteries were placed behind massive reinforced concrete walls about thick, which were in turn behind of earth. Within a few years the armaments of the first phase were obsolete. In 1920, two 12-inch M1895 guns on a new style M1917 barbette carriage that could traverse a full 360 degrees were installed and named after Civil War General Henry Whitney Closson. This design had a projectile with elevation up to 35 degrees and range of. It was located about. Anti-aircraft guns were also added to protect from attack from above. In 1942, concrete shielding was added above the guns. A row of officers' houses was built in 1916, and a chapel added in 1940.