He introduced “glasnost” (openness) and “perestroika” (restructuring) into the Soviet Union, rocking a stagnant and fearful society to its core. Then, he made it clear that the Soviets would not keep the nations of Eastern Europe under their grip, setting off a chain of events that led to the fall of the Berlin Wall and of communist regimes through the region. Finally, much more awkwardly, he oversaw the dissolution of the Soviet Union itself, as it split into 15 nations.

“We are now living in a new world,” he said as he stepped down in December 1991. “An end has been put to the Cold War and to the arms race, as well as to the mad militarization of the country, which has crippled our economy, public attitudes, and morals. The threat of nuclear war has been removed.”

One can debate, as historians and politicians have in the ensuing decades, how much of the change was Gorbachev’s doing and how much was forced on him by the tide of history, as well as leaders like Lech Walesa, Pope John Paul II, and President Ronald Reagan. Certainly, the events of the 1980s — including the humiliating defeat in Afghanistan — had already made it harder for any Soviet leader to continue the nation on its existing path.

But there’s no doubt Gorbachev demonstrated a willingness to accept a much-different Soviet society and a much-different world order, even at the cost of his nation’s power and prestige. Unlike his predecessors, Gorbachev did not cling to a failed dream.

“The selection of Gorbachev was arguably the most revolutionary act in the history of the party since 1917,” wrote historian Orlando Figes in “Revolutionary Russia 1891-1991.” “Had the Politburo known where he would lead the party in the next few years, it would never have allowed him to become its General Secretary.”

Despite their initial mistrust, Reagan and Gorbachev came to be partners in arms control, reversing course on a decades-long arms race. Those international efforts helped Gorbachev’s popularity overseas, at the expense of his reputation back home.

“I was politically active at a time when my country and the whole world were ripe for colossal changes,” he wrote in his book “What Is At Stake Now” in 2020. “We took on the challenges. We made mistakes and misjudged some things. Yet, we initiated changes of historic dimensions, and they were peaceful.”

Mikhail Sergeevich Gorbachev was born March 2, 1931, in an agricultural region. He graduated from Moscow State University in 1955 with a law degree and then launched a career within the Communist Party, rising fast.

He was heavily influenced by Nikita Khrushchev’s denunciation of Josef Stalin and his efforts to bring the party back to the early days of the revolution, under Vladimir Lenin. Nikolai Bukharin, a victim of Stalin’s purges, was another one of his heroes.

Gorbachev also looked to the outside world for ideas. According to Andrew Burstein’s book “Democracy’s Muse,” Gorbachev said during a 1993 visit to Thomas Jefferson’s Monticello in Virginia “that he had returned often, and at critical times, to a college text he had mastered that laid out Jefferson’s political principles.”

The Soviet leadership saw promise in Gorbachev. “The party spotted his talent and clutched him in an embrace,” wrote Victor Sebestyen in “Revolution 1989.” “The party made him — and he was a true believer.”

Sebestyen said Gorbachev had another valuable trait: “Often, people who met Gorbachev came away thinking about him whatever they wanted to believe.”

In 1979, he became a nonvoting member of the Politburo; a year later, Gorbachev was a full member.

In March 1985, Gorbachev ascended to the top spot in the Soviet government, general secretary of the Communist Party’s Central Committee. The nation was badly in need of vigorous leadership, having buried three aged rulers (Leonid Brezhnev, Yuri Andropov and Konstantin Chernenko) in a span of 2 1/2 years. Its military was bogged down in Afghanistan, its populace was impoverished and oppressed, and much of its leadership thoroughly corrupt.

“The tragedy of the Stalin era and the farce of the Brezhnev period represented for Gorbachev not the failure of ideology, but rather its perversion,” wrote David Remnick in “Lenin’s Tomb: The Last Days of the Soviet Empire.”

Gorbachev was 54, a mere pup compared to his wizened comrades on the Politburo.

“Many political observers,” wrote Chris Cviic in the 1986 World Book Year Book, “saw the ascension of Gorbachev as an indication the Soviet ruling class no longer could stand the tension and uncertainty of having frail, elderly individuals at the top.”

Gorbachev, as Figes wrote, was the first Soviet leader to have no connection to Stalin’s monstrous crimes; in fact, members of Gorbachev’s family had been victims of Stalin’s purges. “He sincerely thought that Lenin’s revolution could be made to work through moral and political renewal,” Figes wrote.

American leaders were intrigued by the new leader with the port-wine birthmark on his head — but skeptical. “He will package the Soviet line better for Western consumption,” Vice President George H.W. Bush told Reagan, according to Sebestyen’s book.

The Warsaw Pact nations were also wary, particularly when he told them he wanted them to stand on their own feet. In April 1986, Gorbachev’s government was defensive and secretive about the Chernobyl nuclear disaster, leading many to assume that everything was the same in Moscow.

But change was in motion.

In January 1987, Gorbachev said he wanted history‘s “blank spots” filled in, including an examination of the nation’s bloody past. “History must be seen for what it is,” he told the Central Committee. Truth replaced propaganda.

“The return of history,” Remnick wrote, “to personal, intellectual and political life was the start of the great reform of the 20th century and, whether Gorbachev liked it or not, the collapse of the last empire on Earth.”

In February 1988, Gorbachev called for an overhaul of the Soviet political system. Contested elections were held in March 1989, another awkward new wrinkle. “In place of the Stalinist model of socialism,” he told his nation, “we are coming to a citizens’ society of free people.”

In the name of perestroika and glasnost, the economy was decentralized. “Glasnost has begun to tear the veil that concealed incompetence and a lack of initiative,” wrote Eric Bourne in the 1988 World Book Year Book. Though the KGB was still watching everyone, society began to open up.

Many of Stalin’s victims posthumously had their good names restored, and dissidents regained their rights, including Nobel laureates Andrei Sakharov and Aleksandr Solzhenitsyn. Some of these former dissidents pushed further than Gorbachev and his fellow reformers were ready to go in changing society. “Day by day, the people of the Soviet Union were developing minds of their own,“ Remnick wrote.

Internationally, Gorbachev and Reagan were able to establish a productive rapport, hammering out the Intermediate-Range Nuclear Forces Treaty, a 1987 agreement that eliminated medium-range nuclear weapons. The superpower treaty led to the scrapping of thousands of missiles and warheads, a first.

“With patience, determination and commitment, we’ve made this impossible vision a reality,” Reagan said at the signing, which featured the two leaders joking over a Russian proverb. Western doubters became believers.

“This changed Soviet line was no ruse to disarm us,” national security adviser Colin Powell recalled later of the negotiations. “This man meant what he said.”

On Feb. 15, 1989, the last Soviet troops left Afghanistan, ending a brutal and expensive 10-year occupation.

Meanwhile, the push for change accelerated across the Warsaw Pact nations. On June 12, 1987, by the Berlin Wall, Reagan memorably urged: “Mr. Gorbachev, open this gate. Mr. Gorbachev, tear down this wall.” But at this point, it was more a matter of Gorbachev declining to hold it up.

Speaking to the United Nations in December 1988, Gorbachev disclosed he was cutting the size of the Soviet military and also intended to pull soldiers and tanks out of Eastern Europe. He also spoke of “a truly revolutionary upsurge” within his country. “Under the badge of democratization, restructuring has now encompassed politics, the economy, spiritual life, and ideology,” Gorbachev told the General Assembly. And he praised Reagan and Secretary of State George Shultz.

Writing years later in his book, “Learning from Experience,” Shultz said: “For my money, the real news was the clear tone in which he announced, without really saying so, that the Cold War was over.”

It soon became evident that Gorbachev meant what he said — he had no intention of propping up any satellite regimes. That only served to embolden opposition leaders like Walesa in Poland and Vaclav Havel in Czechoslovakia.

Change came fast. First, Hungary opened its border with Austria in May 1989, then Poland held free elections. Rapid-fire change followed in Hungary, East Germany, Bulgaria, Czechoslovakia, and, finally, reluctantly and violently, in Romania. As the world watched and marveled, the Berlin Wall fell in November 1989. (Serving the KGB in East Germany, a young Vladimir Putin was dismayed by the turn of events.)

In the span of a few months, the unthinkable had become reality, democracy had started to emerge in Eastern Europe and the Cold War had essentially ended. There was no reason to think Gorbachev was unhappy about these developments; he was subsequently awarded the 1990 Nobel Peace Prize.

“The common assumption that the West forced the collapse of the Soviet Union and thus won the Cold War is wrong,” wrote former ambassador Jack Matlock Jr. in the Washington Post in 2014. “The fact is that the Cold War ended by negotiation to the advantage of both sides.”

In his visits to Eastern Europe, Gorbachev had been widely cheered. He hoped these old allies, once they underwent their own reforms, would embrace his nation as a kindred soul. They did not. “Gorbachev failed to see,” wrote Sebestyen, “that the demonstrators were hiding behind him as a way of protesting against their own rulers.”

Amid these startling changes, some in the Soviet Union wanted to turn back the clock. Disgruntled Kremlin bigwigs allied themselves with KGB leaders, top generals, old monarchists and other reactionary elements to undermine Gorbachev. Their plotting then took a sinister turn.

On Aug. 18, 1991, citing unspecified health problems for Gorbachev, Vice President Gennady Yanayev and an emergency committee announced they had assumed power. “He grew very tired over these years, and he will need some time to get better,” Yanayev said of Gorbachev.

It soon became apparent that this was a full-blown coup by remnants of the old power structure. Gorbachev was out of sight, under house arrest at his vacation retreat in the Crimea.

The plotters — whose public face was the consistently inebriated Yanayev — hadn’t counted on widespread public anger fueled by the spirit of glasnost. President Boris Yeltsin led the resistance on Gorbachev’s part in Moscow, and supporters flocked to Yeltsin’s side. The people weren’t willing to accept the old ways.

“It’s terrible. When I heard the news, I fell on the floor,” the Associated Press quoted a “white-haired old woman with weathered hands” in Moscow.

Within 72 hours, the coup had collapsed. “This group wanted to push the people onto a path which would bring our entire nation to a catastrophe,” Gorbachev said on his return Aug. 22. But that same week, he resigned as general secretary of the Communist Party, effectively severing it from the government after more than 70 years.

That final split further emboldened those in the republics who wished to break from the Soviet Union, and soon it was 1989 all over again within Soviet borders. This time, Gorbachev wasn’t pleased — he tried to stymie independence movements in the Baltics and elsewhere. Some protests were met with violence in Lithuania, Latvia, Azerbaijan and Georgia.

By the end of 1991, it was clear there was no holding everything together — one nation split into 15.

“At least in public, Gorbachev seemed to have no idea of where events would lead,” Remnick wrote.

He stepped down Dec. 25, 1991. Gorbachev turned over power — and the Soviet “nuclear button” — to Yeltsin, calling Bush to tell him: “Mr. President, you can spend Christmas evening in peace.”

Years later, Gorbachev would describe his actions as regrettable but necessary. He had hoped that all Soviet citizens would freely choose the Soviet way of life, and they had not. “We were well on the way to a civil war, and I wanted to avoid that,” he told the BBC in 2016.

As Figes would later write: “He was a political Columbus, setting off to find the promised land, only to discover something else.”

Gorbachev became increasingly unpopular, a scapegoat, as Russia continued to evolve under Yeltsin. The loss of empire was disorienting, and the rise of what came to be called “bandit capitalism” demoralizing. The subsequent expansion of NATO into Eastern Europe left Russians feeling humiliated by the West.

In 1996, Gorbachev ran for president against Yeltsin and others across the political spectrum. In the first round of voting, he finished seventh, drawing less than 1 percent. Periodically, he would attempt a comeback; he never got anywhere.

“Russians felt they had lost not an empire or an ideology, but the very essence of their identity,” wrote Shaun Walker in “The Long Hangover: Putin’s New Russia and the Ghosts of the Past.”

In the era of the autocratic Putin, Gorbachev was seen as a weakling.

“In Russia, I am still accused of having ‘given away’ Eastern Europe,” Gorbachev wrote in 2020. “My response to this is: Who did I give it away to? Poland to the Poles, Hungary to the Hungarians, Czechoslovakia to the Czechs and Slovaks!”

Through it all, he remained a visible and widely respected figure in the West, founding the Gorbachev Foundation in 1992.

German filmmaker Wim Wenders used him in his 1993 film Faraway, So Close, and he appeared in a 1997 Pizza Hut ad with his granddaughter, Anastasia. He spoke at Monticello on the 250th anniversary of Jefferson’s birthday. “Freedom is the main idea I learned from Jefferson,” Gorbachev said.

His hefty memoirs were published by Doubleday in 1996, and in February 2004, he shared a Grammy Award with Bill Clinton and Sophia Loren for a spoken-word recording of Peter and the Wolf for children.

Over the years, he received awards in many nations, including the first Ronald Reagan Freedom Award at the former president’s library in California. In 2004, he attended Reagan’s funeral in Washington.

But the West was kinder to him than his own country.

Meeting him briefly in Russia early in his own historic presidency, President Barack Obama found it sad to see how Gorbachev’s nation had discarded him.

“Seventy-eight years old and still robust with the signature red birthmark splashed across his head,” Obama wrote in “A Promised Land,” “he struck me as a strangely tragic figure. Here was a man who’d once been one of the most powerful people on Earth.”

Obama said he had to cut short their conversation to deliver a speech.

“Although he said he understood,” Obama wrote, “I could tell he was disappointed — a reminder for both of us of the fleeting, fickle nature of public life.”