A stunningly large and diverse crowd descends upon New York City’s Central Park on June 12, 1982, demanding nuclear disarmament and an end to the Cold War arms race. By the end of the day, estimates place the number of attendees at over a million, making it the largest disarmament rally in American history.

The United States and the Soviet Union had been in an arms race since World War II, and the Cold War felt particularly hot in the early 1980s. Taking office in 1981, President Ronald Reagan was a staunch proponent of building up America’s nuclear arsenal and vehemently opposed the idea of disarmament treaties. His rhetoric gave new life to the anti-war movement, which had been relatively quiet since its heyday in the late 1960s and early ’70s, when protestors fought against the Vietnam War and accompanying draft. Fearing that Reagan would prefer nuclear war to nuclear disarmament, organizers got to work on a mass demonstration in Midtown Manhattan to coincide with the United Nations Second Special Session on Disarmament.

The rally in Central Park brought together activists from all over the world and all corners of the antiwar movement. Delegations arrived from across North America and and as far afield as Bangladesh and Zambia. Groups of Roman Catholic priests rubbed elbows with rabbis and members of the Communist Party, and protestors’ signs illustrated the range of their political demands: the New York Times recorded posters reading “U.S. Out of El Salvador,” “Houses Not Bomb Shelters,” “A Feminist World Is a Nuclear-Free Zone,'” and, more to the point, “I Hate Nuclear War.” Many called for an immediate end to all nuclear arms programs, but others were less radical, calling simply for the resumption of disarmament negotiations. Activists pointed out the contrast between Reagan’s profligate defense spending and his stingy approach to social programs, and drew connections between the administration’s belligerent attitude toward Russia and its actions in El Salvador, where the CIA was engaged in funding, supplying and coordinating a terror campaign waged by the right-wing Contra rebels. In keeping with its message, the rally was entirely peaceful, and many attendees camped overnight in the park after the crowd began to disperse around 6 p.m.

The 1982 rally and UN special session did not immediately lead to new disarmament treaties, but five years later the U.S. and U.S.S.R. signed the Intermediate-Range Nuclear Forces (INF) Treaty, the first time in history that the superpowers had agreed to shrink their nuclear stockpiles.