St. Peter's Basilica Cornerstone Laid: Rome's Greatest Church Rises

Pope Julius II laid the cornerstone of the new St. Peter's Basilica on April 18, 1506, beginning a construction project that would take 120 years, consume the fortunes of a dozen popes, and inadvertently trigger the Protestant Reformation. The old basilica, built by Emperor Constantine in the fourth century, had stood for over a thousand years but was crumbling beyond repair. Julius, nicknamed "the Warrior Pope" for his military campaigns, envisioned a replacement of unprecedented scale, the largest church in Christendom and a monument to papal authority. The original architect, Donato Bramante, designed a centralized Greek cross plan topped by an enormous dome inspired by the Pantheon. Bramante demolished much of the old basilica with such enthusiasm that critics called him "Bramante Ruinante." He died in 1514 with only the four massive crossing piers completed. Over the next century, a succession of architects, including Raphael, Antonio da Sangallo the Younger, and Michelangelo, revised and expanded the design. Michelangelo, who took over at age 72, designed the dome that would become the basilica's defining feature, though he died in 1564 before it was completed. The staggering cost of construction had consequences far beyond Rome. Pope Leo X authorized the sale of indulgences to fund the building, commissioning Johann Tetzel to sell remission of sins across Germany with the slogan "As soon as a coin in the coffer rings, a soul from purgatory springs." Martin Luther's Ninety-Five Theses of 1517, which attacked this practice, were a direct response to the fundraising for St. Peter's. The church that was meant to glorify Catholicism instead provoked the greatest schism in Western Christian history. The basilica was finally consecrated on November 18, 1626, by Pope Urban VIII. Carlo Maderno had extended Bramante's plan into a Latin cross, and Gian Lorenzo Bernini designed the sweeping colonnade of the piazza outside. The finished structure covers 5.7 acres, rises 448 feet to the top of the dome, and can hold 20,000 worshippers. It remains the largest church in the world and the center of Catholic Christianity, built at a cost that bankrupted popes and broke a church in half.