The Boston Athenæum is one of the oldest independent libraries in the United States. It is also one of several membership libraries, for which patrons pay a yearly subscription fee to use Athenæum services. The institution was founded in 1807 by the Anthology Club of Boston, Massachusetts. It is located at 10½ Beacon Street on Beacon Hill in Boston.

Resources of the Boston Athenæum include a large circulating book collection; a public gallery; a rare books collection of over 100,000 volumes; an art collection of 100,000 paintings, sculptures, prints, drawings, photographs, and decorative arts; research collections including one of the world's most important collections of primary materials on the American Civil War; and a public forum offering lectures, readings, concerts, and other events. Special treasures include the largest portion of President George Washington's library from Mount Vernon; Jean-Antoine Houdon busts of Washington, Benjamin Franklin, and Lafayette once owned by Thomas Jefferson; a first edition copy of John James Audubon's The Birds of America; a 1799 set of Francisco Goya's Los caprichos; portraits by Gilbert Stuart, Chester Harding, and John Singer Sargent; and one of the most extensive collections of contemporary artists' books in the United States.

The Boston Athenæum is also known for the many prominent writers, scholars, and politicians who have been members, including Ralph Waldo Emerson, Nathaniel Hawthorne, Louisa May Alcott, Oliver Wendell Holmes Sr., Oliver Wendell Holmes Jr., John Quincy Adams, Margaret Fuller, Francis Parkman, Amy Lowell, John F. Kennedy, and Edward M. Kennedy.

In 1803, a young Harvard graduate by the name of Phineas Adams established the magazine The Monthly Anthology, or Magazine of Polite Literature. Adams left the New England area in 1804, having insufficient funds to continue the periodical; however, the printers Munroe and Francis convinced other young men to contribute to and continue the magazine under the new title of The Monthly Anthology and Boston Review. By 1805, these young men founded the Anthology Society.

The Boston Athenæum was founded in 1807 by members of the Anthology Society, literary individuals who began with a plan to have a reading room. The first librarian, William Smith Shaw, and the new trustees had ambitious plans for the Athenæum, basing their vision on the Athenæum and Lyceum in Liverpool, England. Their vision was expanded to include a library encompassing books in all subjects in English and foreign languages, a gallery of sculptures and paintings, collections of coins and natural curiosities, and even a laboratory. This ambitious design has developed over the past two hundred years with some changes in focus (e.g., there is no chemistry lab) but remaining true to the ideal expressed in the institution's seal, chosen in 1814: Literarum fructus dulces, meaning "Sweet are the Fruits of Letters."

The first yearly subscriptions were sold for ten dollars; only members had access to the Athenæum's rooms and they were allowed to bring guests. The Athenæum's collections were initially non-circulating, meaning that even members could not check out books to take home.

At first, the Boston Athenæum rented rooms, then in 1809 bought a small house adjacent to the King's Chapel Burying Ground, and in 1822 moved into a mansion on Pearl Street, where a lecture hall and gallery space were added within four years.

In 1823, Shaw stepped down as librarian, and the King's Chapel Library and the Theological Library belonging to the Boston Association of Ministers were deposited in the Athenæum. Work was begun on a shelf catalog in 1827. That same year, the art gallery was established, and the first annual exhibition opened. Measures were undertaken in 1830 to turn the collections into a circulating library. Once the Athenæum became a circulating library, only four books were allowed to be checked out at a time.