On this day in 1987, in one of his most famous Cold War speeches, President Ronald Reagan challenges Soviet Leader Mikhail Gorbachev to “tear down” the Berlin Wall, a symbol of the repressive Communist era in a divided Germany.

In 1945, following Germany’s defeat in World War II, the nation’s capital, Berlin, was divided into four sections, with the Americans, British and French controlling the western region and the Soviets gaining power in the eastern region. In May 1949, the three western sections came together as the Federal Republic of Germany (West Germany), with the German Democratic Republic (East Germany) being established in October of that same year. In 1952, the border between the two countries was closed and by the following year East Germans were prosecuted if they left their country without permission. In August 1961, the Berlin Wall was erected by the East German government to prevent its citizens from escaping to the West. Between 1949 and the wall’s inception, it’s estimated that over 2.5 million East Germans fled to the West in search of a less repressive life.

With the wall as a backdrop, President Reagan declared to a West Berlin crowd in 1987, “There is one sign the Soviets can make that would be unmistakable, that would advance dramatically the cause of freedom and peace.” He then called upon his Soviet counterpart: “Secretary General Gorbachev, if you seek peace–if you seek prosperity for the Soviet Union and Eastern Europe–if you seek liberalization: come here, to this gate. Mr. Gorbachev, open this gate. Mr. Gorbachev, tear down this wall.” Reagan then went on to ask Gorbachev to undertake serious arms reduction talks with the United States.

Most listeners at the time viewed Reagan’s speech as a dramatic appeal to Gorbachev to renew negotiations on nuclear arms reductions. It was also a reminder that despite the Soviet leader’s public statements about a new relationship with the West, the U.S. wanted to see action taken to lessen Cold War tensions. Happily for Berliners, though, the speech also foreshadowed events to come: Two years later, on November 9, 1989, joyful East and West Germans did break down the infamous barrier between East and West Berlin. Germany was officially reunited on October 3, 1990.

Gorbachev, who had been in office since 1985, stepped down from his post as Soviet leader in 1991. Reagan, who served two terms as president, from 1981 to 1989, died on June 5, 2004, at age 93.