The director won the best adapted screenplay Academy Award for "BlacKkKlansman," making it Lee's first competitive Oscar win.
Lee, 61, started out his acceptance speech with some profanity that was silenced for television viewers, reportedly telling producers not to start the clock on his speech.
Lee, an outspoken critic of President Donald Trump, read from a two-page letter that tied together history and the years 1619, when Africans were brought to America on slaveships, and 2019, along with his own story, noting that the "2020 election is right around the corner."
He also urged the audience to side with love over hate.
The writer-director shares the award with Charlie Wachtel, David Rabinowitz, Kevin Willmott.
Jackson ribbed Lee at the outset of his presentation along with actress Brie Larson, reciting the score of the Knicks game, who notched a rare win.
At the conclusion of his speech, Lee exclaimed, "Do the right thing! You know I had to get that in there!"
The Associated Press contributed to this report.