When Pope Francis arrives in Washington, D.C. to kick off his six-day visit to the United States, he’s sure to receive a warmer welcome than the citizens of the nation's capital gave to a papal gift 161 years ago.

Three years after the laying of the Washington Monument’s cornerstone in 1848, Pope Pius IX and the Vatican answered a call to aid in the construction of the obelisk honoring the first American president by announcing plans to donate a marble block harvested from the ruins of the ancient Roman Temple of Concord.

When news of the pending papal contribution reached the United States in early 1852, anti-Catholic nativists were aghast. A backlash sprouted in Philadelphia—another city on Pope Francis' itinerary—where protestors called on the Washington National Monument Society to either reject the donation or install a “protest stone” with a suitable inscription directly on top of the papal rock. “This gift of a despot, if placed within those walls, can never be looked upon by true Americans but with feelings of mortification and disgust,” read one New Jersey petition. A pamphlet published by Baltimore’s John F. Weishampel raised the spectre that the stone was a signal from the pope to launch an immigrant uprising to take over America. “The effects of this block, if placed in the monument, will be a mortification to nearly every American Protestant who looks upon it,” he warned, “and its influence upon the zealous supporters of the Roman hierarchy will be tremendous—especially with foreigners.”

In spite of the protests, the papal stone, inscribed “Rome to America,” eventually arrived in Washington, D.C. During the ensuing months, as the ranks of poor Catholic immigrants from Ireland and Germany grew, so did the anti-immigrant, anti-Catholic forces in the United States dubbed the “Know-Nothings” for their secretive practices.

In the early morning hours of March 6, 1854, a group of nine Know-Nothings in the nation’s capital decided that not only were they going to take their country back, they were going to take the three-foot marble slab donated by Pope Pius as well. As the nightwatchman guarding the Washington Monument construction site read by the light of a lamp, the conspirators wrapped a cord around his shack and piled stones against the door, and it would be two hours before the guard sounded the alarm. They then loaded the “Pope’s Stone” into a handcart and wheeled it a quarter mile to a waiting boat.

The Know-Nothings sailed out into the Potomac River and used a sledgehammer to take chips off the old block as souvenirs. After a lookout stationed on the Long Bridge swung a red lantern as an all-clear signal, the men heaved the mutilated stone overboard, and it splashed to the river bottom.

The Washington National Monument Society offered $500 to anyone with information about the heist, but the Know-Nothings lived up to their moniker and remained tight-lipped for nearly three decades. Not until an anonymous saloonkeeper who was part of the theft told his story to the Washington Post in 1883 was the story revealed. “If the dredges at work in the Potomac strike the right spot, they will fish up something that will create a sensation,” the nameless perpetrator promised, and that’s exactly what happened in 1892 when a diver discovered a beautifully polished piece of pink-and-white marble engraved with most of the letters of “Rome to America” on the muddy river bed. Only two days later, however, the stone was stolen from a construction shack and never seen again.

Today, the 555-foot obelisk still bears the scar of the Know-Nothings’ monumental bigotry. Not only did the secretive group destroy the pope’s gift in 1854, its members also gained control of the board of the Washington National Monument Society itself. Combined with an economic recession, the actions of the Know-Nothings caused donations, particularly from members of the Catholic Church, to dry up. Construction of the Washington Monument halted, and for two decades it remained an unsightly, 153-foot-tall stump that Mark Twain called an “ungainly old chimney.” When work finally resumed in 1878, the marble stones used to complete the obelisk were cut from a different quarry than the originals, causing a subtle, but noticeable, color change in the upper two-thirds of the monument.

Ironically, the actions of the stone-robbers would likely have displeased the man honored by the monument. As commander of the Continental Army, Washington banned the annual practice of burning effigies of the pope on Guy Fawkes Day, calling it a “ridiculous and childish custom.” “To be insulting their religion is so monstrous as not to be suffered or excused,” wrote Washington—who coincidentally was born on the banks of Virginia’s Popes Creek.

A Catholic contribution was finally inserted into the Washington Monument in 1982 when a priest from Spokane, Wash., commissioned a replacement for the Pope’s Stone. Inscribed with the Latin translation of “Rome to America,” the marble block was placed in a staircase wall at the monument’s 340-foot level. [PDF]

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