Cathedrals on Pope Francis’ itinerary reflect American immigration and diversity

The three major Roman Catholic churches that Pope Francis is scheduled to visit during his U.S. tour are steeped in the history of the immigrant experience, a subject close to the pontiff's heart.

The oldest of the three, the Cathedral Basilica of Sts. Peter and Paul in Philadelphia, carries physical reminders of the tumultuous period during which it was built.

The church was constructed in the mid-19th century as waves of immigrants from Ireland, Italy and Germany, many of them Catholics, arrived in the United States. It was also a time when a nativism movement grew among people who believed that the new arrivals threatened the social fabric of the young republic.

Worried that the new, grand cathedral would become a target of street riots stemming from this tension, church leaders included no street-level windows to prevent vandalism. A renovation and expansion in the 1950s added lower windows to a new sanctuary apse and baptistery.

St. Patrick's Cathedral in New York, too, has its origins in the great immigration of the 19th century. It takes it name from the patron saint of Ireland, reflecting the many Irish immigrants who settled in the city. According to a history on the cathedral's website, much of the money raised to build the cathedral came in the form of small contributions from new immigrants.

The identity of the more recently constructed Basilica of the National Shrine of the Immaculate Conception in Washington, D.C., also hones closely to immigrant life in the United States.

Often referred to as "America's Catholic Church," the basilica embraces the diversity of Catholics in the U.S. through the dedication of its 81 chapels to the cultures and countries of its immigrant followers. Among the many nationalities represented in the basilica's chapels are Filipino, Italian, Korean and Mexican.

Pope Francis, himself a descendant of Italian immigrants to Argentina, has made helping immigrants an important issue of his papacy, and of this trip.

The Basilica of the National Shrine of the Immaculate Conception

The Basilica of the National Shrine of the Immaculate Conception, on the campus of Catholic University in Washington, D.C., has 81 chapels dedicated to different nationalities and cultures.

(Mandel Ngan / AFP/Getty Images)

(Getty Images)

The visit: On Sept. 23 the pope will celebrate a Mass on the steps of the basilica's east portico to canonize missionary Junipero Serra.

City: Washington, D.C.

Architecture: Romanesque-Byzantine. The basilica evokes the Byzantine style with its many interior mosaics, while Romanesque architecture is evident in its thick walls and arches. Its most prominent architectural feature is the huge, blue dome that towers over the campus of Catholic University, where it is located.

Opened: Easter Sunday, 1924.

Size: The Great Upper Church, the basilica's main sanctuary, is 399 feet long, 180 feet wide at the transept and 159 feet tall at the Trinity Dome.

Noteworthy event: On Aug. 6, 1966, the basilica was the site of one of the more famous White House weddings, when Luci Baines Johnson, daughter of President Lyndon B. Johnson, married Patrick John Nugent.

Past papal visits: Pope John Paul II in October 1979; Pope Benedict XVI in April 2008.

St. Patrick's Cathedral

Renovations to St. Patrick’s Cathedral in New York are slated to be finished before the pope’s visit.

(Mary Altaffer / Associated Press)

(Associated Press)

The visit: On Sept. 24 the pope will celebrate evening vespers at the cathedral.

City: New York.

The Architecture: Neo-Gothic. The cathedral's two ornately carved spires grace Fifth Avenue in Midtown Manhattan. Inside, the sanctuary is marked by soaring arches and intricate stained-glass windows. It is undergoing a major restoration; a cleaning of its marble exterior, now a gleaming white, was completed in December.

Opened: May 25, 1879.

Size: At its transept, the cathedral measures 174 feet across and 332 feet long. The spires are 330 feet tall.

Noteworthy events: Among the many notable funerals held at the cathedral were Babe Ruth's on Aug. 19, 1948, Robert F. Kennedy's on June 8, 1968, and Andy Warhol's on April 1, 1987.

Past papal visits: Pope Paul VI in October 1965; Pope John Paul II in October 1979 and October 1995; Pope Benedict XVI in April 2008.

Cathedral Basilica of Sts. Peter and Paul

The pope will celebrate a private morning Mass at the Cathedral Basilica of Sts. Peter and Paul in Phlladelphia.

(Don Murray / Getty Images)

(Getty Images)

The visit: On Sept. 26, the pope will celebrate a private morning Mass at the cathedral.

City: Philadelphia.

Architecture: Roman-Corinthian. The cathedral is modeled after San Carlo al Corso, the Lombard Church of St. Charles, in Rome. Its distinctive brownstone facade includes four massive stone columns and its oxidized copper dome is a recognizable landmark in Philadelphia.

Opened: Nov. 20, 1864.

Size: The cathedral is 250 feet long, 136 feet wide, and approximately 156 feet high from the floor to the top of the dome.

Noteworthy event: On Sept. 17, 1982, a memorial Mass was held at the basilica for Princess Grace of Monaco, who was born and raised in Philadelphia.

Past papal visits: Pope John Paul II in October 1979.