Which president met the most popes? Who gave the weirdest gift? A brief history of U.S.-Vatican encounters.

When Pope Francis welcomes U.S. President Joseph R. Biden Jr. to the Vatican tomorrow, it will mark the 31st meeting between a sitting pope and a sitting U.S. president. If that seems like a lot, it’s not: Keep in mind it is only 30 more times than a pope has met Spider-Man. And of those 31 meetings, 29 have been in the last half-century.

The United States did not formally recognize and exchange ambassadors with the Holy See (the name for the Vatican City State in diplomatic terms) until 1984, in part because the United States has never quite known what to make of a political entity that is also a religious headquarters. After all, the Vatican only removed the United States from the category of “mission territory” in 1908, and as late as 1960 John F. Kennedy faced suspicions from U.S. Protestants that a Catholic president would be a double agent for their papal foe.

Perhaps for that reason, President Kennedy waited until 1963 to meet Pope Paul VI in Rome, soon after the latter’s election as pontiff. These days, it is more or less a given that all popes or presidents with length of days in office will meet with each other. And of course, many popes met U.S. presidents before their election as pontiff, especially those who served in the diplomatic corps; similarly, a number of politicians met popes before their election as president—for example, Dwight D. Eisenhower and Pope Pius XII at the close of the Second World War.

The first meeting between a pope and a president was a little more than a century ago, when Woodrow Wilson met Pope Benedict XV in January 1919.

Which pope has met the most presidents? In part because of his long reign and in part because of his many travels, Pope John Paul II holds the crown: Starting with Jimmy Carter in 1979 (in the first visit of a pope to the White House), he also met multiple times with Ronald Reagan, George Bush, Bill Clinton and George W. Bush, both at the Vatican and elsewhere around the world. (He’s also the only pope to meet Bob Dylan).

The first meeting between a pope and a president was a little more than a century ago, when Woodrow Wilson met Pope Benedict XV in January 1919. America assistant editor Joseph McAuley has a detailed account of their meeting, which would likely never have occurred if Mr. Wilson had not arranged for a bit of a victory lap in Europe following the Allied victory in the First World War. Before his attendance at the Paris Peace Conference (which resulted in the Treaty of Versailles, formally ending World War I on June 28, 1919), Wilson spent six months visiting various countries in Europe—at the time the longest period of time any U.S. president had spent outside the country. He met Pope Benedict XV during his visit to Italy, on Jan. 4, 1919. (One can read America’s original account of the meeting here.)

Both men were architects of ambitious peace plans, and both had played significant political roles in the four-year war, but otherwise they had little in common. Wilson spoke German but not Italian; the pope spoke a number of languages but neither German nor English. It didn’t matter, since the diplomatic language of the time was still French, which the pope spoke and the president didn’t. Working through translators, Pope Benedict XV offered a papal blessing to the entourage, resulting in an awkward scene that more than a few historians have used to exemplify the difficulties of navigating the political relationship between the two political entities. The Catholics in Mr. Wilson’s entourage went to a knee for the blessing; Mr. Wilson, the son of a Presbyterian minister, bowed his head instead.

Pope John Paul II would meet five different U.S. presidents on 15 occasions in his 26 years as pope. (He’s also the only pope to meet Bob Dylan).

There would not be another meeting between a sitting pontiff and a president until December 1959, when Dwight D. Eisenhower and Pope John XXIII met at the Vatican. (Joseph McAuley offers a detailed account of the visit in this 2015 America article.) Mr. Eisenhower was about to enter the final year of his two-term presidency. Just the year before, he had sent Pope John XXIII a congratulatory telegram upon his election. Mr. Eisenhower had only been baptized six years before, as a Presbyterian; he had been raised in the Mennonite tradition, which did not practice infant baptism, and he belonged to no denomination until he was baptized 10 days after he was inaugurated in 1953.

Translation was again an issue, as Pope John XXIII was a polyglot but didn’t count English among his many tongues, and Mr. Eisenhower spoke only English. Nevertheless, the two shared a moment of levity that was captured on camera (apparently over Pope John XXIII’s mangling of his prepared speech). The editors of America noted that the pope had “expressed his confidence that the Catholics of the United States would continue to make an exemplary contribution to the maintenance of America’s noble traditions by their ‘action, loyalty and discipline.’ May we not read in these words a papal assurance to the United States that there is no incompatibility between the loyalty of an American Catholic to his religious leader and his duties to his country?”

The next meeting between pope and pontiff would take place not in Rome, but in another city that claimed for itself the mantle of capital of the world: New York City. On Pope Paul VI’s famous visit to the United States in 1965—the first visit of a reigning pope to the United States—he met with President Lyndon B. Johnson. The meeting, wrote Joseph McAuley in America in 2015, had its origins in a private papal audience with Sargent Shriver (a Kennedy-in-law who worked for both Presidents Kennedy and Johnson). Shriver then asked President Johnson if it might be possible for Pope Paul VI to speak before the United Nations (what would become his famous “No more war, war never again!” speech).

Pope Paul VI offered President Johnson a Nativity scene. Mr. Johnson responded by giving the pope a…bronze and plaster bust of himself.

Their second meeting, two years later in Rome, involved a now-famous exchange of gifts. Because it took place two days before Christmas, Pope Paul VI offered President Johnson a Nativity scene. Mr. Johnson responded by giving the pope a…bronze and plaster bust of himself, Lyndon Baines Johnson.

Pope Paul VI would go on to meet with both of Johnson’s successors in office while Paul was still pope: Richard Nixon (twice) and Gerald Ford. (President Nixon, of course, also once met with a very famous king.) With the United States drawn more and more into the Vietnam War, Pope Paul VI’s words to Mr. Nixon at his 1969 visit might have been received as pointed, as the pontiff urged him to put “an even more effective stop to the outbreak of new armed struggles, by following the sure way towards a lasting peace, and promoting true prosperity by means of a widely-based and fruitful understanding.” The United States, the pope said, was called upon to fulfill “a mission of peace, a mission of noble-hearted collaboration with all peoples, and particularly with the developing peoples, in mutual esteem, with respect for the fundamental freedoms of men and of Nations, and in the promotion of genuine human values.”

Pope Paul’s successor, Pope John Paul I, was only in office for 33 days in 1978 before he died. We didn’t even have time to impeach a president, much less send one to Rome.

The next pontiff, Pope John Paul II, would meet five different U.S. presidents on 15 occasions in his 26 years as pope. An informal but nevertheless significant alliance against communism in Europe between him and Ronald Reagan helped to usher in a more copacetic relationship between the Vatican and the U.S. government, and meetings between leaders of the two entities became more common. Pope John Paul II was also the first of the traveling popes; his 104 overseas trips were more than all previous popes combined, and led to numerous meetings outside the traditional New York, D.C. or Rome locales, including Fairbanks, Ak.; St. Louis, Mo.; Newark, N.J.; Miami, Fla.; and Denver, Colo. (at Regis University for World Youth Day in 1993).

After meeting Pope Francis, President Trump took to Twitter (remember when Donald Trump was allowed to use Twitter?!) to call the meeting the “honor of a lifetime.”

Pope John Paul II’s opposition to the United States’ 1991 and 2003 invasions of Iraq made for some fractious meetings during the latter years of his papacy between the pope and U.S. diplomats hoping to get a Vatican stamp of approval. Nonetheless, George W. Bush did present the pope with the Presidential Medal of Freedom during a Rome visit in 2004. The pope noted he had made it very clear in two previous meetings with the president that the “unequivocal position of the Holy See” was to oppose the second U.S. invasion, but also recognized that two decades of diplomatic relations between the two entities “have promoted mutual understanding on great issues of common interest and practical cooperation in different areas.”

When Pope Benedict XVI visited the United States in 2008, it was actually the second time he had met George W. Bush during the latter’s presidency, but was much more memorable because it included an unprecedented speech by the pope on the White House lawn. Taking place on the pontiff’s 81st birthday, the ceremony included an impromptu singing of “Happy Birthday” by the crowd and an enthusiastic, if somewhat colloquial, endorsement from Mr. Bush when he finished his remarks: “Thank you, Your Holiness. Awesome speech.” Pope Benedict was also the first pope to visit the 9/11 memorial in New York City and speak with survivors of the terrorist attacks.

President Barack Obama met with Pope Benedict XVI once and Pope Francis twice, the latter during the pope’s memorable 2015 visit to the United States. The pope’s meeting with Mr. Obama on that occasion was overshadowed by Pope Francis’ address to Congress, where he singled out four prophetic voices from U.S. history: Abraham Lincoln, Martin Luther King, Dorothy Day and Thomas Merton. The trip was also marked by significant U.S. political drama, as House Speaker John Boehner announced his resignation the day after Francis’ address to Congress.

President Donald J. Trump only met Pope Francis once, in Rome, during Mr. Trump’s first foreign trip in 2017, a nine-day affair that included visits to Israel, Palestine and Saudi Arabia. Despite significant disagreements (and public criticism) on issues like immigration, refugees, environmental legislation and economic policies, the two leaders reported an amicable meeting and the Vatican expressed hope for a “positive relationship” with the Trump administration. Afterward, President Trump took to Twitter (remember when Donald Trump was allowed to use Twitter?!) to call the meeting the “honor of a lifetime,” writing that “I leave the Vatican more determined than ever to pursue PEACE in our world.”

President Joseph R. Biden Jr. and Pope Francis have met many times over the course of the last two decades, but tomorrow’s meeting will be the first time the nation’s second Catholic president has met the pope since he was inaugurated. What will they talk about? While questions about pro-choice Catholics like Mr. Biden receiving Communion have been prominent on this side of the pond, America’s Vatican correspondent Gerard O’Connell doubts the issue will come up between the two.

Not only has Pope Francis publicly said that he has never denied someone Communion, but their meeting is also seen more as an opportunity for two global leaders “to focus on the global issues that both leaders consider to be of major concern to humanity at this moment in history,” O’Connell wrote today. Such issues include the Covid-19 pandemic, the climate crisis, global poverty, international human rights, migration and crises in the Middle East. “The agenda may even extend to U.S. relations with China when, after his audience with the pope, President Biden meets Cardinal Pietro Parolin, the secretary of state, and Archbishop Paul Gallagher, the secretary for relations with states,” O’Connell reported.

What gift will President Biden present to Pope Francis? It is safe to bet it will be a historic artifact from American Catholic history, or perhaps a work of art memorializing the relationship between the Holy See and the United States over the last century. Might it be the Biden family Bible on which the president took the oath of office in January?

One thing we’re all hoping it won’t be? A bust of himself.