Fort Adams in Newport, Rhode Island was established on July 4th, 1799 as a First System coastal fortification. Its first commander was Captain John Henry who was later insturmental in starting the War of 1812.

The first Fort Adams was designed by Major Louis Tousard of the Army Corps of Engineers. This fort mounted 12 cannon and was garrisoned during the War of 1812 by Wood's State Corps of Rhode Island militiamen.

After the War of 1812 there was a thorough review of the nation's fortification needs and it was decided to replace the "old" Fort Adams with a newer an much larger fort. The new fort was designed by Brigadier General Simon Bernard, a Frenchman who had served as a military engineer under Napoleon. Bernard designed the new Fort Adams in the classic style of Vauban and it became the complex fortification in the Western Hemisphere.

Construction of the new fort began in 1824 and continued at irregular intervals until 1857. From 1825 to 1838 constrution was overseen by Colonel Joseph Gilbert Totten, the foremost American military engineer of his day. In 1838 Totten became chief engineer of the Army and served until his death in 1864.

The new Fort Adams was first garrisoned in August 1841 and was an active Army post until 1950. During this time the fort was active in five major wars (Mexican War, Civil War, Spanish-American, First World War and Second World War) but never fired a shot in anger.

During the Civil War, Fort Adams was used as the United States Naval Academy. The Academy was moved to Newport from Anapolis in May of 1861, Maryland due to concerns about the political sympathies of the Marylanders. In September 1861 the Academy moved to the Atlantic House hotel in Newport and remained there for the rest of the war.

As time went by, the Fort's armament was upgraded to keep up with technoligical innovations. Major kinds of ordnance used at the Fort included muzzle loading cannon in the 19th Century, breech loading rifled artillery pieces in the early 20th Century and anti-aircraft guns during and after the Second World War.

Fort Adams also served as the headquarters for all fortifications in Narragansett Bay as well as a training center in wartime.

In 1953 the Army gave Fort Adams to the Navy which used the fort's grounds for family housing. In 1965 the fort was given to the state of Rhode Island for use as a state park. In 1974 Fort Adams was declared a National Historic Landmark. In 1994 the Fort Adams trust was formed which provides guided tours at the fort and oversees ongoing restoration work at the fort.