O'Reilly, who's carved out a lucrative niche writing historical blockbusters focused on the bloody deaths of Abraham Lincoln, John F. Kennedy and Jesus of Nazareth, detailed the origins of Santa and declared that Kelly was on the mark.
"In this case, Megyn Kelly is correct. Santa was a white person," O'Reilly said. "Does that matter? No. It doesn't matter."
"The spirit of Santa transcends all racial boundaries," he added.
Kelly claimed on Friday that she was only joking and said the criticism she received was evidence of "the knee-jerk instinct by so many to race-bait."
O'Reilly agreed and argued, as he often does, that Fox's "far left" critics were really motivated by jealousy over the conservative cable news channel's ratings.
"Because they cannot defeat us on the media battlefield, the far left seeks to demonize Fox News as a right-wing propaganda machine and a racist enterprise," O'Reilly said. "That's why Ms. Megyn got headlines about a Santa Claus remark that was totally harmless."