John Gould Stephenson was an American physician and soldier who served as Librarian of Congress from 1861 to 1864. Born in Lancaster, New Hampshire, to a prominent merchant family, he attended education at Dartmouth Medical College and Castleton Medical College, where he received his M.D in 1849. He moved to Terre Haute, Indiana, in the early 1850s, where he became active in the temperance movement and the nascent Republican Party. He campaigned for Abraham Lincoln in the 1859 Senate race in Illinois, at the 1860 Republican National Convention, and in the 1860 presidential election. He pursued an appointment of Librarian of Congress immediately following Lincoln's election, possibly due to his brother's work as a librarian in Cincinnati. After a lengthy pressure campaign, including a number of Indiana officials, Lincoln appointed him as Librarian of Congress, replacing long-term incumbent John Silva Meehan despite opposition from the Joint Committee on the Library.

The librarian of Congress is the head of the Library of Congress, appointed by the president of the United States with the advice and consent of the United States Senate, for a term of ten years. The librarian of Congress also appoints and oversees the Register of Copyrights of the U.S. Copyright Office and has broad responsibilities around copyright, extending to electronic resources and fair use provisions outlined in the Digital Millennium Copyright Act. The librarian determines whether particular works are subject to DMCA prohibitions regarding technological access protection. In addition, the librarian appoints the U.S. poet laureate and awards the Gershwin Prize for Popular Song.