University of California students and sympathizers of the Free Speech Movement are sealed off behind police in front of Sproul Hall in Berkeley on Dec. 3, 1964. (AP)

The University of California at Berkeley has spent the week entangled in controversy after it cancelled a speech by conservative provocateur Ann Coulter, then reversed course Thursday and announced it would allow her to talk on campus early next month.

The decision to prohibit a speaker at any public university would have triggered criticism, but at Berkeley — a symbol of campus free speech in America — it meant much more.

On a December evening in 1964, 1,000 students marched into the Berkley’s Sproul Hall and sat down. The protesters were inspired by the Free Speech Movement, a group demanding, among other things, that the university stop restricting political activity on campus.

The students slept, sang, studied and talked until after 3 a.m., when the chancellor showed up and demanded that they leave, according to news accounts. A few did, but most stayed. Then things turned violent.

“An Army of law officers broke up a massive sit-in occupation,” reported the Associated Press, which described “limply defiant” protesters being dragged down the stairs on their backs and shoved into police vans. “Cries of police brutality rose from demonstration supporters watching outside.”

But university President Clark Kerr had lost his patience with the activists, declaring in a statement that the Free Speech Movement had “become an instrument of anarchy.”

By morning, police had arrested 796 students.

None A Berkley student addresses protesters standing atop the crushed roof of a campus police car during the third day of Free Speech Movement demonstrations in October  1964. (AP)

The school would later relent to the pressure, loosening its rules against political activity on campus and making Sproul Hall a place for open discussion.

The sit-in was one demonstration among several between 1964 and 1965 — including a Vietnam War protest that drew thousands of people — that forever altered activism at U.S. colleges.

“It was the beginning of a seismic shift in American culture,” the San Francisco Chronicle wrote on the 50-year anniversary in 2014, noting that the “energy the FSM unleashed spread through campuses across the country, with protests and ‘takeovers’ everywhere from San Francisco State to the University of Michigan to Columbia and abroad.”

Modern conservatives, including Coulter, are aware of Berkeley’s history — and have seized upon it. Even before the school decided to let her speak on campus in early May, Coulter had promised to go ahead with her speech.

“What are they going to do? Arrest me?” she said Wednesday on the Fox News show “Tucker Carlson Tonight.”

The fear among Berkeley officials stemmed from the upheaval that exploded on campus in February, when violent protests forced university police to cancel a speech by another right-wing firebrand, Milo Yiannopoulos. People set fires, chucked rocks and tossed Molotov cocktails.

The University of California at Berkeley canceled a talk by inflammatory Breitbart writer Milo Yiannopoulos and put the campus on lockdown after intense protests broke out on Feb. 1. (Jenny Starrs/The Washington Post)

On Tuesday night, white nationalist Richard Spencer spoke at Auburn University in Alabama, and protests turned violent there, too, leading to three arrests. Convinced that his racist message would appeal to students weary of politically correct campus culture, Spencer had promised last year to begin giving speeches at universities around the country.

Auburn had attempted to bar his appearance, but U.S. District Judge W. Keith Watkins wouldn’t allow it, writing: “Discrimination on the basis of message content cannot be tolerated under the First Amendment.”

Amid the Berkeley tumult Thursday, Spencer was asked whether he intended to visit that campus, too.

“No immediate plans,” he wrote in a text. “But I feel like I have to now.”

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