This term referred to women kidnapped for the purposes of prostitution and derives from Charles Sumner's 1847 description of the Barbary slave trade.

[3] Other groups like the Woman's Christian Temperance Union and Hull House focused on children of prostitutes and poverty in community life while trying to pass protective legislation.

[6] According to historian Mark Thomas Connelly, "a group of books and pamphlets appeared announcing a startling claim: a pervasive and depraved conspiracy was at large in the land, brutally trapping and seducing American girls into lives of enforced prostitution, or 'white slavery.'

"[7] Such narratives often misleadingly portrayed innocent girls "victimized by a huge, secret and powerful conspiracy controlled by foreigners"[8] as they were drugged or imprisoned and forced into prostitution.

[7] This excerpt from The War on the White Slave Trade was written by the United States District Attorney in Chicago: One thing should be made very clear to the girl who comes up to the city, and that is that the ordinary ice cream parlor is very likely to be a spider's web for her entanglement.

For example, noted radical and feminist Emma Goldman observed, "Whether our reformers admit it or not, the economic and social inferiority of woman is responsible for prostitution.

"[10] Although the law was created to stop forced sexual slavery of women, the most common initial use of the Mann Act was to prosecute men for having sex with underage females.

In addition to its stated purpose of preventing human trafficking, the law was used to prosecute unlawful premarital, extramarital, and interracial relationships.

[12] The 1948 prosecution of Frank LaSalle for abducting Florence Sally Horner is believed to have been an inspiration for Vladimir Nabokov in writing his novel Lolita.

[8] The scope of the Mann Act was expanded in September 1913, as a result of charges brought against Drew Caminetti and Maury Diggs, both of Sacramento, California.

With behavior that was so commonplace now illegal, federal prosecutors had a weapon that could very easily be abused in order to prosecute "undesirables" who were otherwise law-abiding citizens.

For example, the heavyweight champion of the world, Jack Johnson, as well as Charlie Chaplin, and later, Chuck Berry were all prosecuted and convicted under the Mann Act.

The instigating circumstances resulting in prosecution were that Johnson married a white woman,[48] Chaplin had a premarital relationship with a 24 year old actress then later paid her train fare home (crossing over state lines), and Berry paid for transportation of an underage Apache girl to her home, across state lines.

The two women consulted lawyers and then the former mistress unsuccessfully tried to bring charges against him under the Mann Act, attempting to bribe an official to assist in her favor.

The Mann Act continued essentially unchanged until 1978 amendments that expanded coverage to issues around child pornography and exploitation.