T he pioneering work of historians such as Robert Taft, William Welling and Bill Frassanito has contributed to more than just the history of photography as a medium. It has helped establish the photograph as a valuable primary source on par with textual records like news articles and personal correspondence. Historical photographs can provide valuable informa- tion about the topography of a battlefeld, the architecture of a city, and the day-to-day life of a bygone age. In 19th century America, many stereographs and cartes de visite produced for a mass audience carried clues, not only in the image itself, but also im- printed upon the image mount. Te copyright imprint, comprised of the words “Entered According to Act of Congress” followed by the year, registrant name and location information, are a window into a wealth of historical evidence. Decoding that evidence can be difcult without an understand- ing of early American copyright law and its relationship with politics, culture and technology. Tis article considers the period between the frst American Copyright Act in 1790 and the major revision of 1909, bracketing the “long” 19th century by a decade on either side. Te 1790 act based its authority on a clause in the U.S. Constitu- tion and allowed copyright protection for any “map, chart, book, or books.” Just after the turn of the century in 1802, Congress acknowl- edged the unique nature of copyright in image-based mediums by explicitly adding protection for “historical and other prints.” Te next major revision occurred in 1831 at the lobbying of Noah Webster, who sought to double the initial copyright term from 14 to 28 years, and add other provisions for the estates of copyright holders after their deaths. Later that same decade, in a moment of historical serendipity, Samuel F. B. Morse happened to be in France seeking a French patent for his telegraph in early 1839 just as Louis Daguerre announced the discovery of his revolutionary image capturing process. Morse and Daguerre shared their discoveries with each other. Upon his return to New York, Morse lectured on daguerreotypy, which led to rapid difusion of the technology in America. Yet, it would take years for this early image capturing process to mature into what we Entered According to Act of Congress By Jason Lee Guthrie, with images from the Library of Congress Copyright and photography in 19th century America Ainsworth Rand Spofford became the Librarian of Congress in 1864 and began work on a notable campaign of copyright reform that ultimately resulted in the Copyright Act of 1870.