Library of Congress

Born from a wartime loss and rebuilt on Thomas Jefferson's own library, the Library of Congress grew into the largest library in the world — a monument to the Enlightenment conviction that a democracy depends on an informed citizenry.

Congress established its own reference library in 1800 with a $5,000 appropriation, housing roughly 3,000 volumes inside the new Capitol building. That collection was destroyed in August 1814 when British troops burned the Capitol during the War of 1812. Within months, Thomas Jefferson offered his own personal library — nearly 6,500 volumes spanning philosophy, science, and languages far beyond Congress's original legal and reference texts — as a replacement. Congress purchased it in 1815 for $23,950, and Jefferson's expansive, universal conception of knowledge became the philosophical foundation for the library's collecting scope ever since.

By the 1870s the library had again outgrown its Capitol quarters, and Congress authorized a freestanding building. Architects John L. Smithmeyer and Paul J. Pelz won the design competition, with construction beginning in 1886 and interior decoration overseen by Edward Pearce Casey. The result, opened to the public in 1897, was an Italian Renaissance palace of marble, murals, and mosaics — dubbed the 'book palace of the American people' — crowned by the gilded dome of its Main Reading Room.

Later named the Thomas Jefferson Building in his honor, the structure became the anchor of a growing campus: the John Adams Building opened in 1939 and the James Madison Memorial Building in 1980 to house the collection's continued expansion. Today the Library of Congress holds more than 170 million items and functions as the de facto national library of the United States, even as it continues its founding mission of serving Congress.