His downfall came in 2007 when jurors in Chicago found him and other Hollinger International executives swindled shareholders out of more than six million dollars (then worth around £3 million) of their money. But a conviction for felony fraud and obstruction of justice were upheld in 2010 and he was re-sentenced to 42 months in prison and fined $125,000.
It also said that many high-profile individuals had "vigorously vouched for his exceptional character", including Elton John and former USA secretary of state Henry Kissinger, who served on the board of Hollinger International.
In its statement, the White House called him an "entrepreneur and scholar", and said he had made "tremendous contributions to business".
Mr Black, 74, a Canadian-born British citizen, once ran an global newspaper empire that included the Chicago Sun-Times, Britain's Daily Telegraph and the Jerusalem Post. Last year, Black published a biography of Trump, titled Donald J. Trump: A President Like No Other.
"When my assistant said there was a call from the White House, I picked up, said "Hello" and started to ask if this was a prank (suspecting my friends in the British tabloid media), but the caller spoke politely over me: 'Please hold for the president, '" Black wrote in Canada's National Post about receiving news of his pardon from Trump.
"The idea that I would commit a crime is a nonsense", Mr Black told the BBC.
Black, a prolific writer and historian in his own right, vehemently maintained his innocence and launched a series of libel lawsuits in Canada to strike back at the detractors he blames for destroying his once vast empire. They include former secretary of state Henry Kissinger, Sir Elton John, Rush Limbaugh, and the late William F. Buckley Jr.
Sanders said Black is the author of several notable biographies, including volumes on Presidents Franklin D. Roosevelt and Richard Nixon, but she did not mention his book about Trump.
"He could not have been more gracious and quickly got to his point: he was granting me a full pardon that would "Expunge the bad wrap you got".
Lord Black was granted bail pending an appeal against his conviction in 2010, with two of the fraud counts against him overturned in October of that year.