(CNN) The historian Ron Chernow summarized the mood of the 2019 White House Correspondents Association dinner in one sentence.

"We now have to fight hard for basic truths that we once took for granted," he said.

Chernow, the author of the Alexander Hamilton biography that inspired the hit musical "Hamilton," was invited in place of a comedian. The historian was well received as he alternated between clever jokes and a call to arms for democracy.

He only mentioned President Donald Trump by name once, but the President's "enemy of the people" rhetoric came up repeatedly.

"When you chip away at the press, you chip away at our democracy," Chernow said.

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