As Mr Spencer took the stage, most of the half-filled Phillips Centre theatre stood and chanted: “F*** you Spencer!” Many raised their fists in a Black Power salute.
Mr Spencer started by welcoming the crowd to “the most important free speech event of [their] lifetime”. He also thanked university President Kent Fuchs for allowing him to speak on campus.
“For the record, I don’t stand behind racist Richard Spencer,” Mr Fuchs quickly responded on Twitter. “I stand with those who reject and condemn Spencer’s vile and despicable message.”
The university had attempted to bar Mr Spencer from speaking on campus, but relented when he threatened to sure for an infringement of free speech.
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Hundreds of protesters gathered outside to oppose the speech, carrying signs reading “No Nazis UF” and “Resist Fascism”. More than 3,000 people had RSVPed on Facebook to an anti-Spencer protest scheduled for that day.
Florida Governor Rick Scott had also declared a state of emergency, putting the Florida National Guard on standby and allowing the county Sheriff to call on specialised security forces from across the state.
“We live in a country where everyone has the right to voice their opinion, however, we have zero tolerance for violence and public safety is always our number one priority,” he said in a statement.
It was unclear what Mr Spencer intended to discuss in his speech, as he spent the majority of his address shouting down the protesters in the crowd.
“Do you not want to hear something, poor little babies, that might contradict something your professor told you?” he asked. “Might you have to think about something, child?”
The crowd alternated between different chants, from “Go home Spencer!” to “Let’s go Gators!” – a reference to the school’s mascot. The first two rows of audience members, and a scattered few throughout the crowd, cheered Mr Spencer on.
One of the most tense moments came when Mr Spencer discussed the rally in Charlottesville, in which one counter-protester was killed when a car drove into her. Mr Spencer insisted that the facts of the young woman’s death were not yet clear, but the crowd had already erupted in chants.
“It’s your fault!” they called.
Eventually, Mr Spencer decided to turn to a question and answer session.
The first questioner took the microphone and asked: “Why do you think you’re welcome here, when it literally took a court order to get you here?”
“We have a tremendous amount of support–” Mr Spencer said before being drowned out by boos.