Sean “Diddy” Combs was convicted Wednesday of prostitution-related offenses under the federal Mann Act, an anti-sex trafficking law with a controversial, century-old history.

Though he was acquitted of more serious charges, Combs was still convicted of flying people around the country, including his girlfriends and male sex workers, to engage in sexual encounters in felony violation of the federal law.

Over the years, the law has been applied to prominent convictions, including R&B superstar R. Kelly, British socialite Ghislaine Maxwell, musician Chuck Berry and more than a century ago, boxer Jack Johnson. Its broad wording and a subsequent Supreme Court interpretation allowed prosecutors to bring cases against interracial couples, and eventually many others in consensual relationships, according to Cornell Law School's Legal Information Institute.

Here's what to know about the law.

Why is it called the Mann Act?

In 1910, Congress passed the bill, which was named after Republican U.S. Rep. James Robert Mann of Illinois.

It’s also known as the “White-Slave Traffic Act” of 1910.

What's the history behind it?

The 1910 law originally prohibited the interstate or foreign commerce transport of “any woman or girl for the purpose of prostitution or debauchery, or for any other immoral purpose.” It followed a 1907 congressionally appointed commission to look into the issue of immigrant sex workers, with the view that a girl would only enter prostitution unless drugged or held captive, according to Cornell’s Legal Information Institute.

The law was used to secure a conviction against Jack Johnson, who became the first Black boxer to become a world heavyweight champion in 1910. Johnson was convicted in 1913 by an all-white jury for traveling with his white girlfriend, who worked as a sex worker, in violation of the Mann Act.

(President Donald Trump posthumously pardoned Johnson in 2018, saying Johnson had served 10 months in prison “for what many view as a racially-motivated injustice.”)

How has the law changed since 1910?

In a 1917 Supreme Court case, the justices ruled that “illicit fornication,” even when consensual, amounted to an immoral purpose,” according to Cornell’s Legal Information Institute.

A 1986 update made the law gender-neutral and effectively ended the Act’s role in trying to legislate morality by changing “debauchery” and “immoral purpose” to “any sexual activity for which any person can be charged with a criminal offense.”

How does it apply to Combs' case?

In February, Combs' legal team made a motion to dismiss a Mann Act charge, writing that the law “has a long and troubling history as a statute with racist origins, used to target Black men and supposedly protect white women from them.”

The motion says Combs is being singled out because he is a powerful Black man, saying “he is being prosecuted for conduct that regularly goes unpunished.”

He was acquitted of sex trafficking and racketeering charges that could have put him behind bars for life.