Its collections are "universal, not limited by subject, format, or national boundary, and include research materials from all parts of the world and in more than 470 languages".

Congress accepted former president Thomas Jefferson's offer to sell his entire personal collection of 6,487 books to restore the library.

The Library of Congress faced space shortages, understaffing, and lack of funding, until the American Civil War increased the importance of legislative research to meet the demands of a growing federal government.

[7][clarification needed] In 1870, the library gained the right to receive two copies of every copyrightable work printed in the United States; it also built its collections through acquisitions and donations.

[12][13] In August 1814, British forces occupied Washington and, in retaliation for American acts in Canada, burned several government buildings, including the Library of Congress.

[11] Some House members, like New Hampshire representative Daniel Webster, opposed the purchase, wanting to exclude "books of an atheistical, irreligious, and immoral tendency".

While Meehan was a librarian, he supported and perpetuated the notion that "the congressional library should play a limited role on the national scene and that its collections, by and large, should emphasize American materials of obvious use to the U.S.

Three weeks into his term as Librarian of Congress, he left Washington, D.C., to serve as a volunteer aide-de-camp at the battles of Chancellorsville and Gettysburg during the American Civil War.

He began comprehensively collecting Americana and American literature, led the construction of a new building to house the library, and transformed the librarian of Congress position into one of strength and independence.

Between 1865 and 1870, Congress appropriated funds for the construction of the Thomas Jefferson Building, placed all copyright registration and deposit activities under the library's control, and restored the international book exchange.

[37] Putnam also expanded library access to "scientific investigators and duly qualified individuals", and began publishing primary sources for the benefit of scholars.

In 1903, Putnam persuaded President Theodore Roosevelt to use an executive order to transfer the papers of the Founding Fathers from the State Department to the Library of Congress.

On one occasion, Congress initiated an acquisition: in 1929 Congressman Ross Collins (D-Mississippi) gained approval for the library to purchase Otto Vollbehr's collection of incunabula for $1.5 million.

He established a "democracy alcove" in the Main Reading Room of the Jefferson Building for essential documents such as the Declaration of Independence, the Constitution, and The Federalist Papers.

The Library of Congress assisted during the war effort, ranging from storage of the Declaration of Independence and the United States Constitution in Fort Knox for safekeeping to researching weather data on the Himalayas for Air Force pilots.

Further programs included: During Billington's tenure, the library acquired General Lafayette's papers in 1996 from a castle at La Grange, France; they had previously been inaccessible.

It also acquired the only copy of the 1507 Waldseemüller world map ("America's birth certificate") in 2003; it is on permanent display in the library's Thomas Jefferson Building.

[58] These included exhibits on the Vatican Library and the Bibliothèque Nationale de France, several on the Civil War and Lincoln, on African-American culture, on Religion and the founding of the American Republic, the Early Americas (the Kislak Collection became a permanent display), on the global celebration commemorating the 800th anniversary of Magna Carta, and on early American printing, featuring the Rubenstein Bay Psalm Book.

He created the library's first Young Readers Center in the Jefferson Building in 2009, and the first large-scale summer intern (Junior Fellows) program for university students in 1991.

[59] Under Billington, the library sponsored the Gateway to Knowledge in 2010 to 2011, a mobile exhibition to ninety sites, covering all states east of the Mississippi, in a specially designed eighteen-wheel truck.

[60] Billington raised more than half a billion dollars of private support to supplement Congressional appropriations for library collections, programs, and digital outreach.

These private funds helped the library to continue its growth and outreach in the face of a 30% decrease in staffing, caused mainly by legislative appropriations cutbacks.

[63] This followed a GAO report that described a "work environment lacking central oversight" and faulted Billington for "ignoring repeated calls to hire a chief information officer, as required by law.

"[64] When Billington announced his plans to retire in 2015, commentator George Weigel described the Library of Congress as "one of the last refuges in Washington of serious bipartisanship and calm, considered conversation", and "one of the world's greatest cultural centers".

[66][67] In 2017, the library announced the Librarian-in-Residence program, which aims to support the future generation of librarians by giving them the opportunity to gain work experience in five different areas of librarianship, including: Acquisitions/Collection Development, Cataloging/Metadata, and Collection Preservation.

[72] On February 14, 2023, the Library announced that the Lilly Endowment gifted $2.5 million, five-year grant to "launch programs that foster greater understanding of religious cultures in Africa, Central Asia and the Middle East".

[4] Rejected items are used in trades with other libraries around the world, distributed to federal agencies, or donated to schools, communities, and other organizations within the United States.

[6] A 2000 study by information scientists Peter Lyman and Hal Varian suggested that the amount of uncompressed textual data represented by the 26 million books then in the collection was 10 terabytes.

Launched in 1990, it initially planned to choose 160 million objects from its collection to make digitally available on LaserDiscs and CDs that would be distributed to schools and libraries.

The library has kept the "American Memory" name for its public domain website, which today contains 15 million digital objects, comprising over 7 petabytes of data.