A talk by Professor Deborah Lipstadt on Holocaust denial and her legal battle against the notorious revisionist David Irving been viewed over 370,000 times online.
Prof Lipstadt gave the lecture, entitled "Behind the lies of Holocaust Denial" in the UK last month in the UK, as one in a series of prestigious TED talks.
She told her audience that when it came to Holocaust history, “there are facts, there are opinions, and there are lies. Truth is not relative.”
The 15-minute video of the talk has proved a huge hit since it was posted.
The Emory University historian is best known for her successful defence of a libel action brought by Irving in 2000.
Irving sued after Prof Lipstadt labelled him a denier in her book, “Denying The Holocaust: The Growing Assault On Truth And Memory”.
The case was the focus of the film Denial, which was released earlier this year starring Rachel Weisz as Prof Lipstadt.
In her TED talk, the historian criticised the Trump White House and highlighted far-right groups' contempt for evidence and facts.
She said: “We live in an age when truth is on the defensive.”