Book censorship in the United States has occurred since European settlement of New England, though censorship increased in volume and intensity in the 20th and 21st centuries, especially in the 2020s.

The first known instance of book censorship in what is now the United States took place in the 1630s in modern-day Massachusetts, when Puritans sought to outlaw New English Canaan. While specific titles caused bouts of book censorship, with Uncle Tom's Cabin frequently cited as the first book subject to a national ban, censorship of reading materials and their distribution remained sporadic in the United States until the Comstock Laws in 1873. In the early 20th century, book censorship became a more common practice and subject of public debate.

Throughout the 20th and early 21st centuries, there have been waves of attempts at widespread book censorship in the US. Beginning in the 2020s, the country has seen a dramatic increase of attempted and successful censorship, with a 63% rise in reported cases between 2022 and 2023. In recent years, about three-fourths of books subject to censorship in the US are for children and teenagers. In the 21st century, targets of censorship may be print, electronic, or audiobooks, or a curriculum that includes such sources. Targeted texts may be held by a business such as a bookstore; a library, either a public library or one located in a school or university; or the school or university as a whole. The entity requesting censorship may be an organization, private individual, or government official.

In the debate over book censorship in the United States, "freedom to read" proponents cite traditions and legal precedent building upon the Constitution of the United States, particularly the First, Fourth, and Fourteenth Amendments. Over the years, much of the justification for censorship has centered on definitions of obscenity and questions about the perceived moral qualities of various books' content.Steele, Jennifer. (2020). A History of Censorship in the United States. Journal of Intellectual Freedom and Privacy. 5. 6–19. Several professional organizations advocate against book censorship, including the American Library Association (ALA), the National Council of Teachers of English (NCTE), and the American Booksellers Association. Organizations that advocate for removing books from access include Moms for Liberty, No Left Turn for Education, and MassResistance.

Definition and terminology Book censorship is the act of restricting access to books, due to images, ideas, or information contained, because the individual or organization requesting censorship finds the content objectionable. It refers specifically to attempts to remove or curtail access to a work for a whole population – such as all the children at a school or all the patrons of a public library – and does not include an individual's decision that a book is not appropriate for themselves or their dependents.

Book censorship can take a number of forms. Scholar Emily Knox specifies four types of "active" censorship:

Removal: abolishing certain books from the library, classroom, or bookstore shelves; Relocation: moving the specific books to harder-to-access locations within the library, such as creating an "adults only" section; Restriction: limiting access to books or keeping a book in an inaccessible place unless someone gets special permission to view it; and Redaction: striking through or covering sections of materials so they cannot be seen by readers.

Book censorship has often been initiated by a book "challenge," or a request to remove a book from a library or other location. Many libraries and other educational institutions have "reconsideration policies" in place that lay out how to file a challenge and what will happen after one has been filed. These policies exist to make the challenge process transparent and consistent and to support due process. Usually an administrator or a committee will consider the challenge and the text, and make a determination. If the challenge is supported by the reconsideration process, the book will be removed from the library collection, school, etc. A "banned book" is one that has been "removed from a library, classroom, etc." Since 2021, the rise in book challenges nationwide has had a "chilling effect," leading to increased self-censorship (Knox calls this "passive censorship") by many institutions, often at the level of school districts. Additionally, as of 2024, there has been an increase in state and local legislation that normalizes removal, but also relocation and restriction, of books in libraries, schools, and other settings.

History

During the 17th century, a typical form of book censorship in the United States was book burning. What is considered as the first book ban in what is now known as the United States was of Thomas Morton's New English Canaan or New Canaan, published in Amsterdam in 1637. That same year, the Puritan government in Quincy, Massachusetts, banned it because they considered it a heretical and harsh critique of Puritan customs and power structures. In October 1650, William Pynchon's pamphlet, The Meritorious Price of Our Redemption, was criticized and promptly burned by the Puritan government. This book burning in Boston, Massachusetts is often referred to and even considered the "first book burning in America."

On March 3, 1873, United States Congress under the Grant administration passed "An Act for the Suppression of Trade in, and Circulation of, Obscene Literature and Articles of Immoral Use," commonly referred to as the Comstock Law, or Comstock Act. The Act criminalized usage of the U.S. Postal Service to send any of the following items: erotica, contraceptive, abortifacients, sex toys, personal letters alluding to any sexual content or information, or any information regarding the above items. The Act not only restrained the distribution of pornography but also the spread of medical journals that held information regarding contraceptives and abortion. In Washington, D.C., where the federal government has direct jurisdiction, the act also made it a misdemeanor, punishable by fine and imprisonment, to sell, give away, or have in possession any "obscene" publication. Half of the states passed similar anti-obscenity statutes that also banned possession and sale of obscene materials.

The banning of books became more prevalent during the twentieth century as modernist and progressive writers such as James Joyce, Theodore Dreiser, Ernest Hemingway, F. Scott Fitzgerald, and John Steinbeck began their literary careers. Their writing strays greatly from traditionalist literature, the majority of American literature at the time, which depicted good prevailing over evil. These authors did not refrain from revealing their opinions about controversial subject matter. For example, Hemingway's A Farewell to Arms depicts the grim realities of World War I, as well as the story of the two lovers, Frederic Henry and Catherine Barkley, which includes graphic details of a childbirth gone awry. Some cities, including Boston, banned A Farewell to Arms in 1929, labeling the book "salacious."

Boston became a hub of censorship due to the Watch and Ward Society starting with Robert Keable's Simon Called Peter in 1922.Boyer, P. S. (2002). Purity in Print: Book Censorship in America from the Gilded Age to the Computer Age. United States: University of Wisconsin Press. p.172. Despite books not being barred from transmission through the mail, Boston in the 1920s saw the censorship of the magazine The American Mercury, as well as novels such as Elmer Gantry, An American Tragedy, Lady Chatterley's Lover, and the published text of the play Strange Interlude. The rise of censorship in Boston led to books being advertised as "Banned in Boston" to promote sales throughout the rest of the United States. Eventually, the censorship aroused local opposition. An article in a 1929 issue of The Harvard Crimson stated: "it has become so tiresome to reproach Boston for their constant repression of creative work, that we are beginning to surrender in despair." The end of the censorship started in the 1920s when bookstores started to advocate for people's right to read. Finally, in 1933 in Boston, Judge John M. Woosley overturned a federal ban of James Joyce's Ulysses, ruling that the deposition of sex should be allowed in "serious literature". This remained an important distinction for the Comstock Law until 1957 in the court case of Roth v. United States, when the definition became books that were "utterly without redeeming social importance". The power of the Watch and Ward Society was slowly transferred to the municipal authorities that better reflected the demographics of Boston that were "more closely linked to the majority leadership of Boston".

After the wave of censorship, Des Moines Public Library director Forrest Spaulding drafted the Library Bill of Rights in 1938 in order to speak out against "growing intolerance, suppression of free speech and censorship affecting the rights of minorities and individuals". This was revised and adopted by the American Library Association just a year later and has expanded to include application to "book banning, gender and race discrimination and exhibit spaces". This idea was expanded upon in 1953 by a group of professionals who defined the "responsibilities of publishers and librarians to protect Americans’ freedom to read", which has become a known proclamation: "The freedom to read is essential to our democracy".

Another significant aspect of this time was the resurgence of pro-confederacy sentiment, specifically in the southern states of the US. A significant result was the attempt and success of banning specific textbooks, led by the United Daughters of the Confederacy. Their purpose was largely to promote the Lost Cause, through mostly untrue and sometimes completely false claims. One of the earlier textbooks targeted by the UDC was American History by David S. Muzzey. It goes against almost all rules that the Rutherford Committee published in their pamphlet in 1919 to further the Lost Cause narrative. Although the UDC targeted it as early as 1916, the North Carolina textbook commission approved it for use in early 1920. By October, the UDC called for the book to be banned state-wide, even though the contract with the publisher would not come up for renewal until 1922, when it was chosen not to be renewed after public pressure.

The state of Georgia created the Georgia Literature Commission in 1953, which initially described its role as aiding local prosecutors in enforcing the state's obscenity laws. In 1958, it gained the power to issue subpoenas and injunctions to stop publication. It censored hundreds of publications but became less powerful after court rulings against it in the 1960s, and was abolished in 1973.

A wave of book censorship has occurred since 2021. In 2022, a report by the American Library Association found that book censorship had increased to unprecedented levels. The report noted that much of the censorship was directed towards books featuring LGBT and racial minority perspectives, and described a growing trend of harassment and intimidation of librarians.

In August 2023, restrictions have been placed on the teaching of Shakespearean plays and literature by Florida teachers in order to comply with state law.

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