The United States Navy was originally formed as the Continental Navy on October 13th, 1775, though operations had begun before that point. It was formed to fight Great Britain during the Revolutionary War. It achieved mixed results, largely due to the fact that the Royal Navy was more established. The US Navy won some encounters, but lost 24 ships, at one point being reduced to only two ships on active duty. After the war ended the Navy, which was expensive to maintain and had an extremely limited number of uses for the new nation, was disbanded, completely dissolving by 1785. In 1790 the Revenue-Marine was created to enforce trade laws and prevent smuggling.
These were the only armed ships operated by the United States between 1790 an 1798, a period during which American trading ships were frequently attacked by pirates. To deal with these attacks, the Naval Act of 1794 was passed, and six frigates commissioned. This would mark the beginning of the new US Navy.
The first of the six frigates, the USS Constitution, affectionately called Old Ironsides, was launched in 1797. Peace was meanwhile negotiated with Algiers for the return of seamen captured by the Barbary pirates. Relations with France, however, were declining. The United States took a policy of neutrality, a policy which placed them at loggerheads with both the French and the British, who were presently at war with one another. From 1794 onwards the French had begun to take arms against the US, capturing some 300 ships in the next three years. The Quasi-War was begun in 1798, and fought entirely at sea, mainly involving privateers and merchant ships. That same year doubts about the ability of the War Department to handle a Navy in wartime led to the creation of the Department of the Navy. The US Navy, fighting its first battles, saw many success during this war, which lasted until 1800.
In 1799 the Royal Navy began with earnest to press-gang US sailors into the Royal Navy, which was highly illegal. Approximately 10,000 sailors were recruited to the Royal Navy this way. In 1801 the First Barbary War was begun, and the Navy, acting in concert with the US Marine Corps, was central in the eventual victory in 1805. After the war the size of the Navy was again reduced for cost reasons. During this time the Royal Navy continued their illegal press-ganging of US sailors. Tensions began to climb significantly after 1807, when the USS Chesapeake sustained heavy damage after refusing to allow HMS Leopard to conduct an "inspection". These tensions eventually led to the US declaring war on Great Britain in 1812.
At the beginning of the war, the US Navy was woefully outmanned by the Royal Navy. However, the US Navy still had a number of victories, capturing a number of British ships. In 1813 they were engaged in a successful raiding venture in the South Pacific, but by 1814 they had been largely blockaded by the British Navy. They did win two battles, at Lake Champlain and Lake Erie, that prevented the British from taking full control of the Great Lakes.
After the war, instead of declining in size, the Navy's accomplishments were rewarded with increased funding. They began construction of large ships, but the cost proved prohibitive and most were left in half-completed states until another war began. The Navy mostly operated on large frigates and sloops, slowly transitioning into steam-powered ships in the 1840s. During this time they were involved in the Second Barbary War, begun in 1815, ended that same year in an American victory. Also during this time they were involved in the combat of piracy in the Caribbean, which continued through to the 1830s. Between 1845 and 1848 the Navy was involved in the Mexican-American War. The United States Naval Academy was established in 1851 to ameliorate the poor training issues that had thus far been endemic to the US Navy.
In 1861 the South seceded from the Union, kicking off the American Civil War. Almost 400 sailors left the Navy to join the Confederacy. In the early months of the war they scuttled a number of ships, but in such a haphazard way as to allow the South to resurrect at least one of them. They established a blockade, and were first engaged in 1862 in a battle that ended in a draw. They spent a great deal of the war dealing with blockade runners. Despite the efforts of the blockade runners, the Union blockade slowly but surely placed a stranglehold on the Confederacy, and hastened the end of the war, which came in 1865.
After the war, the Navy again entered a period of decline, mostly for economic reasons. 1871 saw a small part of the greatly reduced fleet involved in a skirmish with Korea over the deaths of several shipwrecked sailors. By this point almost all of its fleet had been depleted and in 1873 it was realized that the Navy had no ship capable of defeating an ironside, causing the commission of several new ships. The Navy continued in a sorry state into 1881, when the new government began to focus on revitalizing it.
1882 saw the first request for new ships, eventually granted in 1883. Three protected vessels and one dispatch ship were created, followed by two further protected vessels in 1885. During this period the first two American battleships were constructed. By 1890 the Western Frontier had been largely explored, and the Navy became the new instrument for Manifest Destiny as the interests of the United States turned increasingly outwards. The Navy Act of 1890 allowed the creation of three more battleships, and by 1900 two Kearsarge class battleships and three Illinois class battleships had been added to the fleet, ranking the US Navy fifth in the world.
The Spanish-American War began in April 1898, though the Navy had been quietly positioned for attack even before war was declared. They were responsible for the decisive defeat of the Spanish flotilla in the Battle of Manila Bay and the Battle of Santiago de Cuba. They were instrumental in the American success in the war.
In 1901 Theodore Roosevelt was elected. An enthusiastic supporter of the Navy, he expanded the surface fleet as well as bringing new technological innovations in, although the first submarine had been commissioned in 1900. In 1907 he commissioned sixteen new battleships, which formed his Great White Fleet that embarked on a cruise of the world. This cruise served the dual purpose of training a number of naval officers, and to prove to the rest of the world that the US Navy was not to be taken lightly.
In the early years of the First World War, the United States maintained a policy of neutrality. The Germans waged unrestricted U-boat warfare against England, occasionally targeting ships flying American colours. This resulted in the sinking of the USS Gullflight and the USS Lusitania in 1915, a move which eventually brought the US into the war, and at first caused them to contemplate increasing the funding for the Navy. After the US entered in the war in 1917, the Navy was mostly restricted to escorting convoys, transporting troops and laying minefields in the North Sea. They are notable as the first branch of the US military to allow women to enlist in a non-nurse capacity.
By the end of the war the Navy was the largest in the world, with over 500,000 officers and enlisted personnel. They were briefly demobilized, and in 1921 a series of treaties were signed limiting, among other things, the use of submarine warfare. It also limited the size of member nations' navies, causing the US Navy to scrap several ships. Instead they began to develop light cruisers and aircraft carriers, the first of which was commissioned in 1922. A year previously, the Bureau of Aeronautics was formed, creating the United States Naval Air Corps. In 1929 the Great Depression caused most countries to limit their spending on ship building, including the US. Nonetheless, the Navy maintained a presence in the East through the 1930s, at the Philippines and near China. 1937 saw the creation of the first new battleship since 1921, and in 1940 and 1941 the Navy expanded to about 200 more ships. In 1941, as the US crept closer to war, the Atlantic Fleet was reactivated.
On December 7th, 1941, the Japanese attacked the naval base at Pearl Harbor. This drew America into the war. The Navy fought mainly in the Pacific Theater, where it was involved in the immensely successful island hopping campaign, though they were also involved in the European Theater, in some of the major landings of the war. During this time the Navy grew immensely, operating just over 6,700 ships by August of 1945.
After this, however, a large number of ships were scrapped or mothballed as the traditional war ended and the tensions of the Cold War began. However the Korean War, which began in 1950, quickly ended this practice, and strategic placement of fleets around the world began. However, the Navy did not participate much in the war itself. Through the 1950s the technological prowess of the Navy was well-known, and they focused on developing nuclear power for ships, and missiles and jets specifically for the use of the Navy. During the Vietnam War, which began in 1968, the Navy participated in the form of aircraft carriers and small gunboats that patrolled in the rivers. Although they continued to play an active part in the war, the construction of new ships was limited, and the total size of the Navy dwindled to just over 300 ships and submarines. However, the growth of the Soviet fleet troubled the US administration, and by 1988 it had climbed to 588, though in subsequent years began to decline again. In 1988 they fought in the Persian Gulf against Iran.
After the Cold War ended in 1991, the Soviet Navy collapsed, leaving the US Navy as the largest and most powerful in the world. Its power continued to grow, though its size shrank. By 2005 there were just over 300 ships in the Navy, though they were far more powerful than their predecessors. In 2007 it adopted a new maritime strategy that advocated prevention of war. As of 2010 the fleet continued to shrink, as did budgets, increasing demands on the Navy, leaving them to rely on international allies.
The US Navy is administered by the Department of the Navy, and is headquartered at The Pentagon. It is divided into nine parts, the Fleet Forces Command, Pacific Fleet, Naval Forces Central Command, Naval Forces Europe, Naval Network Warfare Command, Naval Reserve, United States Naval Special Warfare Command, Operational Test and Evaluation Force, and Military Sea Lift Command. Currently there are six active numbered fleets, the Second, Third, Fifth, Sixth and Seventh. Currently there are 430,300 personnel in the Navy, along with 289 ships, upwards of 3,700 aircraft, 11 aircraft carriers, 75 submarines and 138 other kinds of ship.