“But what do we mean by the American Revolution? Do we mean the American war? The Revolution was effected before the war commenced. The Revolution was in the minds and hearts of the people; a change in their religious sentiments of their duties and obligations.”

— John Adams, “Letter to Hezekiah Niles,” Feb. 13, 1818

What John Adams observed about the American Revolution of the 1770s was also true about the Polish Revolution of the 1980s that helped bring about the end of the Cold War.

Before there was a Solidarity trade union with 10 million members that ultimately toppled Soviet Communism, there was a revolution in the minds and hearts of the Polish people that made Solidarity possible.

In August 1980, striking shipyard workers in Gdansk, Poland, sparked a wave of strikes across the entire country. They demanded the reinstatement of fired shipyard worker Anna Walentynowicz, better working conditions and the right to form independent trade unions.

The strike ended peacefully on Aug. 31, 1980, when the workers and the government signed a landmark agreement that included the right to form independent trade unions.

Two weeks later, Solidarity was born, and within 16 months more than 10 million Poles joined.

Nine years later, in June 1989, Solidarity candidates won overwhelming victories in the first semi-free elections in Soviet-occupied Eastern Europe in 40 years and formed the first non-communist-led government in the Eastern bloc. Five months later, the Berlin Wall fell, and, in December 1991, the Soviet Union disappeared.

But what was the revolution in the Polish hearts that led them so decisively to embrace Solidarity and endure nine years of hardship, including martial law and murder, to see this peaceful revolution through to fruition?

It became evident to my wife, Callista, and me while working on the documentary film Nine Days That Changed the World that spiritual factors were decisive, especially the nine-day pilgrimage of Pope John Paul II to Poland in June 1979, just 14 months prior to the August 1980 strikes.

As the world joyfully celebrated the beatification of Pope John Paul II on May 1 and remembered and celebrated his life of holiness, it’s worthwhile to remember how his Christian witness also fundamentally reshaped the political landscape of the 20th century.

We learned about the significance of John Paul II’s 1979 pilgrimage during a trip to Europe in 2008, when we were conducting interviews for our documentary Ronald Reagan: Rendezvous With Destiny. We traveled to Gdansk, Poland, to interview President Lech Walesa, and then to Prague to visit with President Vaclav Havel.

Both presidents described the Pope’s role as critical and agreed that his 1979 pilgrimage to Poland was a decisive turning point in undermining communism.

President Walesa recalled that when Poles “felt so totally discouraged and so helpless, there came John Paul II. … He awoke the people. … He organized the people.”

In his famous sermon before 1 million Poles assembled in Warsaw’s Victory Square on June 2, 1979, the Pope asserted that man cannot understand himself fully without Jesus Christ and that “therefore, Christ cannot be kept out of the history of many in any part of the world.”

The people responded with 14 minutes of applause and in one voice sang Christus vincit, Christus regnat, Christus imperat (Christ conquers; Christ reigns; Christ governs), dramatically affirming that God was sovereign, not the state.

When asked to explain the meaning of these 14 minutes of applause, Wladyslaw Stasiak, chief of staff to Polish President Lech Kaczynski, said:

In this [sermon], the Pope gave meaning to words, gave meaning to history, gave meaning to the faith of the people. … That was the rebirth. The Pope said the words have their proper meaning. If you are talking about something, it means something. If you are talking about Jesus Christ, it means that you are really talking about Jesus Christ. If you are talking about this country, you really cannot understand this country without Jesus Christ, without Christianity. This was something fundamental. This was something which deeply, very deeply, radically, changed the way of thinking of the majority of the society.

Millions of Poles, almost one-third of the nation, turned out to see Pope John Paul II in person during his June 1979 pilgrimage, while the rest of the country followed his pilgrimage on television and radio.

Polish historian Marek Lasota is unequivocal about the impact of the pilgrimage:

Solidarity, there is no doubt in anybody’s mind, is the result of the Pope’s pilgrimage of 1979. These hundreds of thousands, or millions, of people that met together in Warsaw, Gniezno, Czestochowa, Krakow, Nowy Targ, Wadowice and also Auschwitz understood that this [Solidarity] is the right road. That really, when we’re all together, we are a force, and the enemy [the communists] is helpless.

In his sermon on the last day of his 1979 pilgrimage, Pope John Paul II summed up the great choice that lay before his Polish countrymen and women:

A human person is a free and reasonable being. He or she is a knowing and responsible subject. He or she can and must, through the power of personal thought, come to know the truth. He or she can and must choose and decide. … So, before going away, I beg you once again to accept the whole of the spiritual legacy which goes by the name of “Poland,” with the faith, hope and charity that Christ poured into us at our holy baptism. Do not on your own cut yourselves off from the roots from which we had our origins.

Two years later, the verdict was in. Notwithstanding the power of propaganda and state-sponsored terror, more than 10 million Poles signaled that they would seek change in their country by pursuing the path of social solidarity with faith, hope and charity. The Solidarity labor union and social movement achieved a peaceful revolution in 1989 that toppled Poland’s communist dictatorship, and ultimately hastened the downfall of all the other dictatorships across Eastern Europe.

But the Polish revolution of 1989 was first won in 1979, with the words of Pope John Paul II and the change in moral conviction within the hearts of the Polish people that his words, prayers and pilgrimage inspired.

Former House Speaker Newt Gingrich and his wife, Callista, are hosts and executive producers of the documentary film Nine Days That Changed the World.