President Donald Trump issued a pardon for boxer Jack Johnson, a decision that he said was partially due to actor Sylvester Stallone bringing the issue to his attention.

“We have done something today that was very important because we righted a wrong. It was a wrong, and a lot of people knew it,” the president said after signing the pardon on Thursday. “Jack Johnson was not treated fairly and we have corrected that.”

Linda Haywood, the maternal great-great niece of Jack Johnson was present for the ceremony that took place in the Oval Office.

“My family, now, can go forward knowing that the shame and the pain has been erased, and history will be rewritten,” Haywood said to Trump. “And I sincerely thank you, sir.”

Although he was the first black heavyweight world champion of boxing, Jackson had a difficult history, convicted of violating the Mann Act by transporting a woman across state lines “for immoral purposes” while he had relationships with white prostitutes. Jackson fled the country to escape prison but returned in 1920 to serve his sentence, spending ten months in prison. He died in a car accident in 1946 at the age of 68.

“I am taking this very righteous step, I believe, to correct a wrong that occurred in our history, and to honor a truly legendary boxing champion, legendary athlete, and a person that, when people got to know him, they really liked him and they really thought he was treated unfairly as a human being and unfairly as a champion,” Trump said at the event.

A posthumous pardon for Jackson has drawn the support of many political leaders, including Sens. John McCain and Harry Reid. In 2015, Congress passed a resolution supporting the pardon. Former Presidents, George W. Bush and Barack Obama did not issue a pardon, despite requests from lawmakers and influential promoters of the sport of boxing.

“No president ever signed it, surprisingly,” Trump said. “They thought it was going to be signed in the last administration and that didn’t happen, so that was very disappointing for a lot of people.”

“It’s incredible you’ve done this,” Stallone said to Trump, adding that Johnson was the inspiration for the boxing character Apollo Creed in his Rocky movies.

“He’s truly an inspirational character,” he said. “This has been a long time coming.”

Current world heavyweight champion Deontay Wilder was present for the event, as well as three-time world heavyweight champion Lennox Lewis and WBC heavyweight champion Deontay Wilder.

“On behalf of the world of boxing, I would like to praise, congratulate, and thank you for taking this gigantic step for human equality and inclusion,” Mauricio Sulaiman Saldivar, president of World Boxing Council said calling the event “a great day for the sport” and “a great day for humanity.”