When Boston was founded on the Shawmut Peninsula in 1630, the South End was only a narrow isthmus of land connecting the town of Boston to the mainland. Charles Bulfinch, architect of the Massachusetts State House and later the United States Capitol, laid out the South End's first street plan in 1801 as a grid pattern of streets surrounding a large oval-shaped park called Columbia Square (today's Blackstone and Franklin Squares).

Early map of Boston showing the original South End as 'Boston Neck' and Washington Street as the narrow artery connecting the mainland and the town of Boston. Courtesy of the Society for the Preservation of New England Antiquities.

Boston's burgeoning population outgrew the original peninsula in the 1840s, pressing the city to fill in the Back Bay and South Bay marshes on each side of the isthmus.

Chester Square, Union Park, and Worcester Square were created during the 1850s to attract Boston's mercantile class to the South End, and soon handsome brick bowfront townhouses surrounded the London-style squares. Later, Columbus Avenue was built in the Parisian boulevard style in 1868, reflecting the shift to French urban design. 1883 Map of Boston, with the South End and Back Bay landfills completed. Washington Street, which travelled up the original neck, is highlighted. From King's Handbook of Boston, published 1885. Courtesy of Richard O. Card.

The South End has a rich social and architectural history, but in the 20th century the neighborhood suffered from neglect, arson, and wholesale demolition. By the mid-1970s, about one quarter of the original buildings had been destroyed.

In 1966, concerned citizens founded The South End Historical Society to preserve the area for future generations. In 1972, the South End was placed on the National Register of Historic Places as the largest Victorian brick rowhouse district extant in the United States.

In 1983, the area became a local Boston Landmark District and is the largest landmark district in the country, covering more than 500 acres.