ROME – Although Pope Francis once again appears to be coming through a surgery with flying colors, it’s still inevitable that his second hospitalization in three months, this time for an operation to repair an abdominal hernia, nevertheless has stirred renewed interest in what will happen whenever the end does finally come.

One key figure at that time will be the Camerlengo. Historically, the Camerlengo governed the Catholic Church during the sede vacante after one pope dies or resigns, and before another is elected. Today his powers are more limited, but he remains the Acting Sovereign of the Vatican during the interregnum.

The current Camerlengo, for the record, is an American: Cardinal Kevin Farrell, who thus is in line to become the first American ever to be the Vatican’s sovereign, however nominal and temporary the gig may be.

The assignment is one of five important roles Farrell holds in this papacy. The others are:

• Prefect of the Dicastery for Family, Laity and Life, the first of the Vatican’s new “mega-departments” to be created by Pope Francis.
• President of the Vatican City State’s Corte di Cassazione, in effect its civil Supreme Court, a nomination he received June 2.
• President of the “Commission for Reserved Matters,” a body created by Pope Francis to oversee sensitive financial contracts that fall outside the Vatican’s public transparency systems.
• Chair of the Investments Committee, another new body which oversees the Vatican’s investment portfolio.

Although Farrell was born in Dublin, he was incardinated into the Archdiocese of Washington in 1984, has spent most of his career in the United States and identifies as an American. It’s thus ironic that under a pope many observers regard as ambivalent about Americans, this particular American has amassed such a remarkable range of authority.

RELATED: Latest Vatican gig cements Farrell as Francis’s favorite American

Farrell’s ascent invites the admittedly somewhat playful question of where he now ranks among the most powerful Americans of all time in the Vatican.

In making that assessment, we have to face the fact that Vaticanology isn’t like sports, where there are statistics and championships to evaluate, or politics, where one can look at election results and legislative accomplishments.

Alas, the Vatican is trickier.

Titles, for instance, don’t tell you much. Cardinals Joseph Ratzinger and Luis Ladaria both have been Prefect of the Congregation for the Doctrine of the Faith, but nobody would contend that Ladaria today is as important to the Francis papacy as Ratzinger was to John Paul II.

Similarly, hierarchical levels can also be misleading. The cardinal who runs the Congregation for Religious technically outranks the archbishop who’s the sostituto, or “substitute,” in the Secretariat of State, but few Vatican-watchers would suggest that makes the cardinal the more powerful figure. Indeed, you don’t even have to be a cleric … under John Paul II, for example, few figures were more central than Spanish layman Joaquin Navarro-Valls.

Likewise, job descriptions only take you so far. You can Google what the assessore, or “assessor,” is supposed to do in the Secretariat of State, but it will only scratch the surface of the actual roles played by Archbishop Peter Wells when he held the post under Popes Benedict XVI and Francis.

There’s also sometimes a gap between perception and reality. There are figures seen as having tremendous entrée – sometimes, to be honest, they do everything in their power to cultivate those impressions – but who aren’t actually all that influential. Meanwhile, there are others who deliberately maintain a low profile, but who nevertheless move the levers of power.

As a result, assessing relative importance is terribly inexact, and no two Vaticanisti likely would come up with the same list. That subjectivity, however, is also part of the fun.

It probably goes without saying, but just to be clear: This is not a moral analysis, as in, which American had the best or most positive influence on the Vatican? Instead, it’s a political science question: Which American has wielded the most actual power in the Vatican at his or her peak, regardless of whether you agree with how they used it?

In that sense, here’s my own personal list of the ten most influential Americans in the Vatican of all time … let the debates begin!

10. Myron Taylor, Pope Pius XII

A onetime textiles tycoon and executive with U.S. Steel, Taylor was named the personal envoy to Pope Pius XII by President Franklin Roosevelt in 1939, a position he would hold until 1950, serving under President Harry Truman as well. Among other things, Taylor is credited with helping persuade Spain’s Franco not to join the Axis powers. During the war years, Taylor helped influence the Vatican’s attitude towards the Allies, and in the immediate post-war years he helped coordinate relief efforts with both the Vatican and the American government.

9. Cardinal John Wright, Pope Paul VI

A Massachusetts native, Wright became the private secretary to both Cardinal William O’Connell and Richard Cushing of Boston and later served as Bishop of Pittsburgh. He became Prefect of the Vatican’s Congregation for Clergy in 1969 and held the position until his death a decade later, helping shape efforts to implement the Second Vatican Council (1962-65) with regard to the priesthood.

8. Archbishop Peter Wells, Popes Benedict XVI/Francis

Wells became head of the Secretariat of State’s English language desk in 2006, before being made assessore, or “assessor,” meaning the third most powerful figure for internal church affairs, in 2009. During his tenure, Wells was the primary point of contact for virtually every English-speaking individual, organization or cause that had dealings with the Vatican. He now represents the pope to Cambodia, Thailand and Laos, and is considered a credible candidate one day to become the Vatican’s first American Secretary of State.

7. Cardinal James Harvey, John Paul II

In the John Paul years, Harvey as Prefect of the Papal Household was part of a troika of figures who flanked the pope, including Archbishop (later Cardinal) Stanislaw Dziwisz as John Paul’s private secretary and Archbishop Piero Marini as the Master of Liturgical Ceremonies. Though Harvey’s role was never really policy-making, he nonetheless acted as a critically important gatekeeper and emissary. Today he’s the Archpriest of the Basilica of St. Paul Outside the Walls.

6. Archbishop Paul Marcinkus, Popes Paul VI/John Paul II

A native of Cicero, Illinois, the onetime beachhead of Al Capone, Marcinkus was a close friend of Italian Monsignor Giovanni Battista Montini, who later became Pope Paul VI. Marcinkus served as an interpreter and advisor to Paul VI and helped organize his overseas trips. John Paul II later made him president of the Institute for the Works of Religion, better known as the “Vatican bank,” where Marcinkus presided over the celebrated Vatican bank scandals of the 1980s.

5. Mary Ann Glendon, Popes John Paul II/Benedict XVI/Francis

Glendon, a law professor at Harvard often tipped as potential Supreme Court nominee, became the first lay woman to head a Vatican delegation at an international conference during the highly contentious 1995 U.N. Conference on Women at Beijing. She was named President of the Pontifical Academy for Social Sciences in 2000, and in 2007 she was appointed U.S. Ambassador to the Holy See. In 2013, Pope Francis tapped Glendon for a commission to study an overhaul of the Vatican bank, and in 2014 she became the lone member of that body to be named to the new Board of Directors for the bank.

4. Cardinal Kevin Farrell, Pope Francis

We’ve already noted the various positions to which Farrell has been named. It’s worth noting the other figures Francis recently picked for the same Vatican court: Cardinals Matteo Zuppi of Bologna, Paolo Lojudice of Siena-Colle and Mauro Gambetti, the pope’s Vicar General for the Vatican City State, Archpriest of St. Peter’s Basilica and President of the Fabric of St. Peter. That’s an all-star lineup of this pope’s most trusted inner core of allies and advisors …and even in that set, Farrell came out on top.

3. Cardinal William Levada, Pope Benedict XVI

A Long Beach native, Levada worked from 1976 to 1982 in the Vatican’s Congregation for the Doctrine of the Faith, where he caught the eye of the new prefect who took over in 1981, Cardinal Joseph Ratzinger of Germany. He went on to serve as the Archbishop of both Portland and San Francisco before being named Prefect of the Congregation for the Doctrine of the Faith by his old boss Ratzinger, now Pope Benedict XVI. In that role, among other tasks, Levada had the lead responsibility for implementing the Vatican’s new, more rigorous approach to the clerical sexual abuse crisis. Levada was also named to the Congregations for Bishops, Saints, Evangelization, Oriental Churches and Catholic Education, as well as Pontifical Councils for Legislative Texts, Christian Unity and New Evangelization.

2. Cardinal Edmund Szoka, Pope John Paul II

The son of Polish immigrants to Michigan, Szoka rose through the clerical ranks and became Archbishop of Detroit in 1981, among other things welcoming John Paul II to the Motor City in 1987. In 1990, John Paul turned to his fellow Pole to save the Vatican from drowning in red ink as President of the Prefecture of the Economic Affairs of the Holy See and also President of the Government of the Vatican City State, in both cases becoming the first American to hold the job. During his tenure, John Paul made Szoka a member of virtually every Vatican department that mattered, including the Secretariat of State and the Congregations for Bishops, Clergy and Evangelization.

And now, drum roll please …

1. Cardinal Justin Rigali, Pope John Paul II

The descendant of Italian immigrants from Tuscany and a native of Los Angeles, Rigali studied in Rome during the Second Vatican Council and then began working in the Secretariat of State in 1964, serving in the Vatican for a robust 30 years. He became head of the English section in 1970, often serving as a papal translator and ghostwriter. For almost a decade, from 1985 to 1994, then-Bishop Justin Rigali held an astonishing range of positions that mattered under Pope John Paul II. In June 1985, he became President of the Pontifical Ecclesiastical Academy, responsible for training Vatican diplomats at the height of the Cold War, when the Vatican’s geopolitical relevance under the Polish pope was at an all-time high. He would later become secretary, meaning the number two official, in the Congregation for Bishops and would also serve as Secretary to the College of Cardinals. At various points, he held influential positions with the Council for Public Affairs of the Church and the Pontifical Council for Laity, and was a member of the Interdicasterial Commission of the Holy See, the Pontifical Commission for Latin America and the Congregation for the Doctrine of the Faith. Though Rigali’s legacy would later be tainted by debates over the abuse crisis and also financial management as the Archbishop of Philadelphia, for a period of time Rigali held sway in the Vatican as no American before or since ever has.

Finally, a rundown of honorable mentions who didn’t quite make my cut, in no particular order.

• Cardinal Francis Spellman of New York, a personal friend of Pope Pius XII who helped guide the church through WWII and the Cold War.
• Cardinal Sean O’Malley of Boston, a member of Pope Francis’s Council of Cardinals and also President of the Pontifical Commission for the Protection of Minors.
• Sister Sharon Holland, who served in the Congregation for Religious for more than 20 years before retiring in 2019, much of that time as one of the few women to hold the rank of capo ufficio, or “office head.” A skilled canon lawyer, she helped guide religious orders around the world in reforms in the wake of the Second Vatican Council (1962-65).
• Cardinal Raymond Burke, President of the Apostolic Signatura and a member of the Congregation for Bishops under Pope Benedict XVI.
• Cardinal John Krol of Philadelphia, a son of Polish immigrants and a key informal advisor to Pope John Paul II.
• Cardinal John Foley, who headed the Vatican’s Pontifical Commission for Social Communications from 1984 to 2007.
• Cardinal Bernard Law of Boston, an important American point of reference during the John Paul years until the eruption of the abuse scandals.
• Ex-Cardinal (and ex-priest) Theodore McCarrick, who, as the Archbishop of Newark and later Washington, cultivated Vatican relationships.
• Archbishop Charles Brown, who worked in the Congregation for the Doctrine of the Faith from 1994 to 2012, then served as the papal ambassador to Ireland, Albania and the Philippines.
• James Nicholson, former head of the Republican National Committee who served as President George W. Bush’s first Ambassador to the Holy See.
• Carl Anderson, former Supreme Knight of the Knights of Columbus.
• Jeffrey Lena, a California-based attorney who’s represented the Holy See on sex abuse cases in American courts and also served as a key advisor to Pope Francis on various legal reform issues.
• Lewis Cass Jr., personal emissary of the United States to the Papal States from 1848 to 1854. Among other things, Cass had to navigate the rise of the short-lived Roman Republic in 1848 and the flight of Pope Pius IX to Gaeta, where Pius (technically) became the first pontiff to set foot on American territory by boarding the USS Constitution to deliver a blessing and hand out rosaries to Catholic sailors.

Okay, Vatican affairs junkies everywhere: What did I get wrong?