In Salt Lake City's early days, Brigham Young once mediated a property dispute between a Roman Catholic priest and another fellow.
The LDS Church president sided with the priest and even offered, according to a contemporary newspaper account, to donate $500 for a school and church planned for the site.
That 1867 gesture set the tone for most -- though certainly not all -- of the interactions between Mormons and Catholics in ensuing years.
According to historians, the Latter-day Saints who settled the Salt Lake Valley and the Catholics who began joining them in the 1860s generally had a live-and-let-live relationship.
"During those days, the Catholics and Mormons were operating on two separate tracks pretty much," says Gary Topping, archivist for the Catholic diocese of Salt Lake City. However, he adds, "there was always a little sniping going on."
The predominant Mormons were building their Zion while the Catholics planted parishes, schools and Holy Cross Hospital.
Salt Lake City's first Catholic bishop, Lawrence Scanlan, had hoped the schools he started would lead to conversions among LDS children, Topping says. "He was disabused of that pretty quickly."
Murals take on Mormonism » Sometimes, relations were downright ecumenical.
Topping recently found a 1923 letter in the archives of the Utah State Historical Society from a Salt Lake City doctor to a friend who was away from the city for a time.
The physician blamed a typographical error on weariness, but he had a good excuse: He had been playing poker until 3 a.m. with an attorney and the leaders of three churches -- LDS President Heber J. Grant, Catholic Bishop Joseph Glass and the Rev. Elmer Goshen of the First Congregational Church.
Yet it was Glass, Salt Lake City's second Catholic bishop, who directly took on doctrinal differences with the LDS Church in a bold way: the murals at the Cathedral of the Madeleine.
Above the altar, along with the vibrant paintings of saints, Glass had the artist add scriptural passages that can be taken as defenses of the Catholic faith against other Christians' claims, Mormons in particular.
On the right is the passage from St. Paul's letter to the Galatians that reads: "Though we or an angel from heaven preach a gospel to you besides that which we have preached to you, let him be anathema."
To the left is a passage from Matthew in which Jesus tells Peter that the gates of hell will not prevail against his church. Catholics believe Peter was the first pope, the "rock" upon which Christ's church was built.
A central LDS doctrine is that the early Christian church fell into apostasy, necessitating a restoration centuries later. Church founder Joseph Smith said Angel Moroni led him to gold plates from which he translated The Book of Mormon in bringing back Christ's gospel.
Other scriptures on the cathedral's walls are a defense of the distinct Catholic belief that each Mass is a holy sacrifice, and the bread and wine become the true body and blood of Christ.
"It's obvious," Topping says. "Of all the scriptural passages he could have chosen, he chose those that take on the LDS most frontally."
Yet Monsignor J. Terrence Fitzgerald, vicar general of the diocese, sees the murals more as evidence that Glass wanted to teach Utah Catholics basic tenets of their faith. The murals, he adds, are in keeping with the centuries-old tradition that a cathedral teaches the faith.
Fitzgerald says Mormons and Catholics were at arm's length for much of the 20th century, partly because that's how Catholics wanted it.
Before the church's bishops at Vatican II in the early 1960s decided Catholics should engage with the world, he notes, Catholics were discouraged from attending weddings and funerals of people from other faiths.
Cold war deepens » The low point for relations came in the 1940s and '50s, according to Topping and Gregory Prince, who wrote an article on that era for the spring 2005 Journal of Mormon History.
The first crisis came when a priest who was editor of the Catholic newspaper, The Intermountain Catholic, wrote about Fawn Brodie's unflattering biography of Joseph Smith, No Man Knows My History, and the official LDS reaction to the book, Topping and Prince write.
The priest's column was filled with barbs. LDS leaders protested. Catholic Bishop Duane Hunt then quietly removed the priest from the editorship.
Not long afterward, the LDS-owned radio station KSL offered Hunt free airtime to discuss the Catholic faith on a weekly Sunday evening show. Back in 1930, he had paid for time for such a show, but this segment aired the same evening as one hosted by J. Reuben Clark, first counselor to the LDS president. Soon, Clark was accusing Hunt of declaring theological war on the Mormons.
An editorial about Utah's high divorce rate in The Salt Lake Tribune and a pamphlet Hunt published to raise money for Catholic missions in Utah further stoked the standoff.
Prince, who lives in Maryland and is LDS, says his initial research pointed to Hunt spoiling for a fight with Mormons. Prince is the co-author of the 2005 book David O. McKay and the Rise of Modern Mormonism.
"The more I looked into it, I thought Hunt was a real saint. This man bent over backward," Prince says. "For the most part, the Mormons were dissing him."
McKay, who became LDS president in 1951, was conflicted about Catholics, Prince says. Although he had warm, friendly relations with many individuals, including Hunt, McKay privately distrusted the Catholic Church and even referred to it once in his journal as a "godless farce."
Prince writes that McKay told another LDS apostle the Catholic Church ranked with communism as one of the world's two great anti-Christs.
A hard McConkie, a softer McKay » The lowest point came in 1958 when LDS general authority Bruce R. McConkie wrote an encyclopedic book, Mormon Doctrine, which identified the Catholic Church as the "church of the devil" and the "most abominable above all other churches."
Hunt apparently went to a new LDS congressman with tears in his eyes, saying Catholics didn't deserve such treatment and took the matter to McKay himself, according to the Topping and Prince article.
McConkie's book was revised in the next edition, Prince says, and McKay seemed changed.
"He never said it directly, but I think McKay was so upset by the negative impact of McConkie's book that it jolted him into believing he had been part of the problem," Prince says. "He quietly reversed field. After that, he never again was negative to Catholics, privately or publicly."
When Hunt died unexpectedly in 1960, McKay attended his funeral in the cathedral. And when McKay died a decade later, Hunt's successor as Catholic bishop, Joseph Lennox Federal, had the cathedral bells toll as the hearse carrying the Mormon leader's body passed by.
In the decades since then, relations between leaders in the LDS and Catholic faiths have been generally warm. During the past 20 years, in particular, they have teamed up on a number of charitable and humanitarian causes.
Elder M. Russell Ballard, a member of the Quorum of the Twelve Apostles, says he deeply values his friendships with current Catholic Bishop John C. Wester and his predecessors.
"Each has bettered our community with their service," Ballard says. "Over the years, we've been able to identify shared concerns, encourage unity and lend a hand to those in need."
He calls the Cathedral of the Madeleine, dedicated 100 years ago on Aug. 15, "an architectural gem and a spiritual beacon in the city."
Wester sees the cathedral as a "symbol of our relationship with other religions, the community and anybody, frankly, who comes through our doors." He points to the concerts and other arts events staged there as evidence of Catholic outreach.
"We have relationships with other people of God," he says. "We are gifted in being in this community. The cathedral is our way of giving back or returning the gifts we've received, working hand in hand with other faiths, predominantly the LDS faith, to enhance the arts."
Tribune reporter Peggy Fletcher Stack contributed to this story.