The midshipmen and faculty returned to Annapolis just after the war ended in the summer of 1865.

From the Civil War to World War I
Civil War hero, Admiral David Dixon Porter became superintendent in 1865. He found the infrastructure at Annapolis a shambles, the result of ill military use during the War. Porter attempted to restore the facilities. He concentrated on recruiting naval officers as opposed to civilians, a change of philosophy. He recruited teachers Stephen B. Luce, future admirals Winfield Scott Schley, George Dewey, and William T. Sampson. He reinstated Professor Lockwood. The midshipmen battalion consisted of four companies. They held dress parades every evening except Sunday. Students were termed "cadets", though sometimes "cadet midshipmen;" and other appellations were used. Porter began organized athletics, usually intramural at the time.^[13]
In 1867, indoor plumbing and water was supplied to the family quarters. In 1868, the figurehead from the USS Delaware, known as "Tecumseh" was erected in the yard. Class rings were first issued in 1869. Weekly dances were held. Wags called the school "Porter's Dancing Academy." President U.S. Grant distributed diplomas to the class of 1869.^[13] Porter ensured continued room for expansion by overseeing the purchase of 113 acres (46 ha) across College Creek, later known as hospital point.
In 1871, color competition began, along with the selection of the color company, and a "color girl."^[13]
In the 1870s, cuts in the military budget resulted in graduating much smaller classes. In 1872, 25 graduated. Eight of these made the Navy a career.^[13] The third class physically hazed the fourth class so ruthlessly that Congress passed an anti-hazing law in 1874. Hazing continued in more stealthy forms.^[13]
John H. Conyers of South Carolina was the first black admitted on September 21, 1872.^[14] After his arrival, he was subject to severe, ongoing hazing, including verbal torment, and beatings. His classmates even attempted to drown him.^[15] Three cadets were dismissed as a result, but the abuse, including shunning, continued in more subtle forms and Conyers finally resigned in October 1873.^[16]
In 1875, Albert Michelson, class of 1873, returned to teach. He began his experiments with light along the Severn River.^[13]
In 1874, the curriculum was altered to study naval topics in the final two years at the academy. In 1878, the academy was awarded a gold medal for academics at the Universal Exposition in Paris.^[13]
The Spanish-American War of 1898 greatly increased the academy's importance and the campus was almost wholly rebuilt and much enlarged between 1899 and 1906.
In 1912, the Reina Mercedes, sunk at the Battle of Santiago de Cuba, was raised and used as the "brig" ship for the academy.^[17]
In 1914 the Midshipmen Drum and Bugle corps was formed and by 1922 it went defunct. They were revived in 1926.^[18]
Many firsts for minorities occurred during this period. In 1877, Kiro Kunitomo, a Japanese citizen, graduated from the academy.^[19][20] And then in 1879, Robert F. Lopez was the first Hispanic-American to graduate from the academy.
In the late 19th century, Congress required the academy to teach a formal course in hygiene, the only course required by Congress of any military academy. Tradition holds that a congressman was particularly disgusted by the appearance of a midshipman returned from cruise.

World War I to World War II

The navy rowing team won the gold medal at 1920 Summer Olympics Games held in Antwerp, Belgium. In 1923 The Department of Physical Training was established. The naval academy football team played the University of Washington in the Rose Bowl tying 14–14. In 1925 the second-class ring dance was started. In 1925 the Midshipmen Drum and Bugle Corps was formally reestablished.^[18] In 1926, "Navy Blue and Gold", composed by organist and choirmaster J. W. Crosley, was first sung in public. It became a tradition to sing this alma mater song at the end of student and alumni gatherings such as pep rallies and football games, and on graduation day. In 1926 Navy won the national collegiate football championship title. In the fall of 1929 the Secretary of the Navy gave his approval for graduates to compete for Rhodes Scholarships. Six graduates were selected for that honor that same year. The Association of American Universities accredited the Naval Academy curriculum on 30 October 1930.
In 1930, the class of 1891 presented a bronze replica of Tecumseh to replace the deteriorating wooden figurehead that had been prominently displayed on campus.^[13]
President Franklin D. Roosevelt signed into law an act of Congress (Public Law 73-21, 48 Stat. 73) on 25 May 1933 providing for the bachelor of science degree for Naval, Military, and Coast Guard Academies. Four years later, Congress authorized the superintendent to award a bachelor of science degree to all living graduates. Reserve officer training was re-established in anticipation of World War II in 1941.
The academy was certified in 1937 by the Middle States Association although with reservations about the academic climate.^[21]
In 1939, the first yard patrol craft arrived. These were used to train midshipmen in ship handling.^[22]
In 1940, the academy stopped using the Reina Mercedes as a brig for disciplined midshipmen, and restricted them to Bancroft Hall, instead.^[17]
In April 1941 superintendent Rear Admiral Russell Willson refused to allow the school's lacrosse team to play a visiting team from Harvard University because the Harvard team included a black player. Harvard's athletic director ordered the player home and the game was played on 4 April, as scheduled, which Navy won 12–0.^[23]
A total of 3,319 graduates were commissioned during World War II. Dr. Chris Lambertsen held the first closed-circuit oxygen SCUBA course in the United States for the Office of Strategic Services maritime unit at the academy on 17 May 1943.^[24][25] In 1945 A Department of Aviation was established. That year a Vice Admiral, Aubrey W. Fitch, became superintendent. The naval academy celebrated its centennial. During the century of its existence, roughly 18,563 midshipmen had graduated, including the class of 1946.^[26]

World War II to present
The academy and its support facilities became part of the Severn River Naval Command from 1941 to 1962.^[27]
An accelerated course was given to midshipmen during the war years which affected classes entering during the war and graduating later. The students studied year around. This affected the class of 1948 most of all. For the only time, a class was divided by academic standing. 1948A graduated in June 1947; the remainder, called 1948B, a year later.^[21]
From 1946 to 1961, N3N amphibious biplanes were used at the academy to introduce midshipmen to flying.^[28]
On 3 June 1949 Wesley A. Brown, the sixth African-American to enter the academy,^[15] became the first to graduate, followed several years later by Lawrence Chambers, who would become the first African American graduate to make flag rank.^[29]
The Navy eight-man rowing crew won the gold medal at 1952 Summer Olympics in Helsinki, Finland. They were also named National Intercollegiate Champions.^[30] In 1955, the tradition of greasing Herndon Monument for plebes to climb to exchange their plebe "dixie cup" covers (hats) for a midshipman's cover started.
In 1957, the Reina Mercedes, ruined by a hurricane, was scrapped.^[17]
The Navy-Marine Corps Memorial Stadium, funded by donations, was dedicated 26 September 1959.
Joe Bellino (class of 1961) was awarded the Heisman Trophy on 22 June 1960. In 1961 the Naval Academy Foreign Affairs Conference was started. The Department of the Interior designated the U.S. Naval Academy a National Historic Landmark on 21 August 1961. In 1963, Roger Staubach, class of 1965, was awarded the Heisman Trophy.
In 1963, the academy changed from a marking system based on 4.0 to a letter grade. Midshipmen began referring to the statue of Tecumseh as the "god of 2.0" instead of "the god of 2.5", the former failing mark.^[31]
The academy started the Trident Scholar Program in 1963. From 3 to 16 juniors are selected for independent study during their final year.^[32]
Professor Samuel Massie became the first African-American faculty member in 1966. On 4 June 1969 the first designated engineering degrees were granted to qualified graduates of the class of 1969.^[33] During the period 1968 to 1972, the academy moved beyond engineering to include more than 20 majors. In 1970, the James Forrestal Lecture was created. This has resulted in various leaders speaking to midshipmen, including Henry Kissinger, football coach Dick Vermeil, and Supreme Court Justice Antonin Scalia.^[34]
The 1970s brought change. In 1972 Lieutenant Commander Georgia Clark became the first female officer instructor, and Dr. Rae Jean Goodman was appointed to the faculty as the first civilian woman. Later in 1972, a decision of the United States Court of Appeals for the District of Columbia terminated compulsory chapel attendance, which had been in effect since 1853.^[35] In September 1973, the library facility complex was completed and named for Fleet AdmiralChester W. Nimitz class of 1905.
On 8 August 1975, Congress authorized women to attend service academies. The class of 1980 was inducted with 81 women midshipmen. In 1980 the academy included "Hispanic/Latino" as a racial category for demographic purposes; four women identified themselves as Hispanic in the class of 1981, and these women become the first Hispanic females to graduate from the academy: Carmel Gilliland (who had the highest class rank), Lilia Ramirez (who retired with the rank of commander), Ina Marie Gomez, and Trinora Pinto.^[36] In 1979 "June Week" was renamed "Commissioning Week" because graduation had moved to May.^[37]
In May 1980, Elizabeth Anne Belzer (later Rowe) became the first woman graduate. On 23 May 1984, Kristine Holderied became the first woman to graduate at the head of the class. In addition, the class of 1984 included the first naturalized Korean-American graduates, all choosing commissions in the U.S. Navy. The four Korean-American ensigns were Walter Lee, Thomas Kymn, Andrew Kim, and Se-Hun Oh.
On 30 July 1987, the Computing Sciences Accreditation Board (CSAB) granted accreditation for the Computer Science program.^[38] In 1991, Midshipman Juliane Gallina, class of 1992, became the first woman brigade commander. On 29 January 1994, the first genderless service assignment was held. All billets were opened equally to men and women with the exception of special warfare and submarine duty. On 12 March 1995, Lieutenant Commander Wendy B. Lawrence, class of 1981, became a mission specialist in the space shuttle Endeavor. She is the first woman USNA graduate to fly in space.
To celebrate the 150th Anniversary of the U.S. Naval Academy at Annapolis (1845-1995), the U.S. Post Office printed a postage stamp; the First Day of Issue was 10 October 1995.
Freedom 7, America's first space capsule, was placed on display at the visitor center as the centerpiece of the "Grads in Space" exhibit on 23 September 1998. The late Rear Admiral Alan Shepard, class of 1945, had flown Freedom 7 116.5 miles (187.5 km) into space on 5 May 1961. His historic flight marked America's first step in the space race.^[39]
On 11 September 2001, the academy lost 14 alumni in the terrorist attacks on the World Trade Center and The Pentagon. The academy was placed under unprecedented high security.^[40]
In August 2007, Superintendent Vice Admiral Jeffrey Fowler changed academy policy to limit liberty, required more squad interaction to emphasize that "we are a nation at war."^[41]
On 3 November 2007, the navy football team defeated long-time rival Notre Dame for the first time in 43 years – 46–44 in triple overtime. The two teams have met every year since 1926 and continue a rivalry that became amicable when Notre Dame volunteered to open its facilities for training of naval officers in World War II.^[42] The Navy was credited with saving the University of Notre Dame after its enrollment fell during World War II to about 250 students. The navy trained 12,000 men to become officers.^[43]
In November 2007, Memorial Hall was the venue for a 50-nation Annapolis Conference on a Palestinian-Israeli peace process.

Rank structure
The student body is known as the Brigade of Midshipmen. Students attending the U.S. Naval Academy are appointed to the rank of Midshipman and serve on active duty in that rank. A naval academy midshipman is classified as an officer of the line, though their exercise of authority is limited by their training status.^[44] Legally, midshipmen are a special grade of officer that ranks between Warrant Officer (W-1) and the lowest grade of Chief Warrant Officer (W-2). However, midshipmen are not entrusted or authorized to exercise Title 10 or Title 50 authority as specified in United State Code.^[44][45]
Midshipmen are classified not as freshmen, sophomores, juniors, and seniors, but as fourth class, third class, second class, and first class.
A member of the entering class—the Fourth Class, the lowest rank of midshipman—is also known as a "plebe" (plural, "plebes"). Because the first year at the Academy is one of transformation from a civilian into a military officer, plebes must conform to a number of rules and regulations not placed on their seniors—the upper three classes of midshipmen—and have additional tasks and responsibilities that disappear upon promotion to midshipman third class.