Dover was founded in 1683 by William Penn as a court town for the new Kent County, then formally laid out in 1717 by Thomas Penn around a public square known simply as The Green. The Green sits at the geographic heart of downtown Dover and has functioned continuously as a public space for over three centuries. The Delaware General Assembly first met there in 1777. The Delaware Constitution was signed there in 1792. On December 7, 1787, Delaware ratified the U.S. Constitution at The Golden Fleece Tavern facing The Green - the first state to do so, an act the state celebrates every December. Today the Legislative Hall sits at the south end of The Green. Loockerman Hall, the home built around 1742 by Nicholas Loockerman and now part of Delaware State University, still stands a mile south. Dover's colonial architecture is preserved by tight historic-district zoning and the long-term work of Mabel Lloyd Ridgely, the suffragist and preservationist who in the 1930s organized the cataloguing of the colonial buildings that survived. The Green remains the kind of public square most American cities lost decades ago.

Dover Air Force Base sits in the southeast corner of the city limits, home to the 436th and 512th Airlift Wings flying C-5 Super Galaxy and C-17 Globemaster III strategic transports. The base also houses the Charles C. Carson Center for Mortuary Affairs - the only port mortuary in the continental United States. Every American service member killed overseas comes home through Dover. The arrangement is somber and unusual: a small American city carries the responsibility of receiving the war dead. The economic profile of Dover combines the base with the state government, Kent County offices, and several major manufacturers. Kraft Foods makes the Jell-O. Procter and Gamble makes Pampers Baby Fresh wipes at a plant on the southern edge of town. ILC Dover, in nearby Frederica, produced the spacesuits worn by every Apollo astronaut who walked on the moon - including the Neil Armstrong suit now displayed at the Smithsonian - and has continued as the prime contractor for Skylab, Space Shuttle, and ISS extravehicular spacesuit assemblies. A city that ends each day with a military funeral salute also ends it with chocolate pudding from the same factory that made Apollo moon suits possible.

Annie Jump Cannon was born in Dover on December 11, 1863. Her father was a Delaware state senator. Her mother taught her to identify the stars from the family's attic on State Street. Cannon went on to attend Wellesley College, then joined the Harvard College Observatory in 1896 as one of the women computers - the all-female team that catalogued and classified the stars from glass photographic plates. In a career spanning forty years at Harvard, Cannon personally classified more stars than anyone in history. She refined the spectral classification scheme into what is still known as the Harvard Classification Scheme - the OBAFGKM sequence that astronomy students still memorize using mnemonics about Oh Be A Fine Girl Kiss Me. Cannon was the first woman to receive an honorary doctorate from Oxford and the first woman officer of the American Astronomical Society. The Annie J. Cannon Award for Astronomy still goes annually to an early-career female astronomer in the AAS. The astronomical history of stellar classification runs through a Delaware politician's daughter who learned the constellations from an attic in Dover.

Dover Motor Speedway hosts a NASCAR race weekend every May. The Monster Mile - the one-mile, high-banked concrete oval - has been a NASCAR fixture since 1969 and was a stop on the Cup Series schedule until the schedule was reorganized in 2021. The races still draw around 65,000 spectators, though attendance has fallen significantly from the 140,000 that filled the track in the 1990s and 2000s. Adjacent to the speedway sits Bally's Dover, a harness racing track, hotel, and casino - the harness oval is actually inside the NASCAR oval. From 2012 through 2018, the Firefly Music Festival ran in the Woodlands adjacent to the speedway, drawing about 90,000 fans for four days of major rock and pop acts (Paul McCartney, Eminem, Arcade Fire). The festival paused after 2018, returned briefly in 2021 and 2022, then went on hiatus again after 2023 with no confirmed return date. NASCAR and Firefly briefly made Dover the largest summer entertainment destination on the Delmarva Peninsula. The festival's end left the speedway as the dominant venue, with the country's other major NASCAR ovals further south. Race weekend remains the highest revenue weekend on the local economic calendar.

Dover is one of only four state capitals in the United States not served by an Interstate highway - the others are Pierre, South Dakota; Jefferson City, Missouri; and Juneau, Alaska. The closest Interstate is I-95, more than 50 miles north in Wilmington. Dover is also the only state capital with a volunteer fire department - the Dover Fire Department has served the city since 1882 with all-volunteer personnel and two stations. West of Dover sits an Amish community of about 1,650 people across eleven church districts. The Amish first settled in Kent County in 1915. The community nearly disappeared in the 1920s and 1930s as families moved away, then rebounded from the 1960s onward. Buggies share the road with NASCAR fans. Amish farms supply the produce stands along Forrest Avenue. The city has the cultural texture of a colonial capital absorbed into the modern economy: state archives in colonial buildings, the country's only military port mortuary at one end of town, the Jell-O plant at another, an Amish settlement on the western edge, and a NASCAR oval on the east. A small place, with a complicated identity, holding the political center of America's second-smallest state.