St. Peter’s Basilica, an iconic symbol of Vatican City and a major pilgrimage site for Catholics worldwide, is renowned for its breathtaking Renaissance and Baroque architecture and its profound historical significance. Understanding when this monumental structure was built requires delving into a fascinating timeline spanning over a century, involving numerous popes, architects, and artistic visions. The answer to “When Was St Peter Basilica Built” is not a single date, but rather a period of dedicated construction from the early 16th century to the early 17th century, building upon earlier foundations and ambitions.
The story of St. Peter’s Basilica begins long before its current magnificent form. In the 15th century, Pope Nicholas V recognized the dilapidated state of Old St. Peter’s Basilica, the original church believed to be built by Emperor Constantine in the 4th century. Centuries of history had taken their toll, with walls leaning precariously and frescoes obscured by dust. Driven by a vision to restore the glory of the Vatican and create a fitting shrine for St. Peter the Apostle, Pope Nicholas V initiated plans for a new basilica in 1452. He entrusted Bernardo Rossellino to begin constructing a new apse to the west of the old basilica. However, this initial momentum was halted by Nicholas V’s death, and the project was paused.
Later, in 1470, Pope Paul II revived the ambitious undertaking, entrusting Giuliano da Sangallo with the project. These early efforts laid some groundwork, but the true commencement of the New St. Peter’s Basilica, the structure we recognize today, is marked by a pivotal moment on April 18, 1506. It was on this date that Pope Julius II laid the first stone, officially launching the construction of what would become one of the most significant buildings in human history. Pope Julius II envisioned a grand basilica in the form of a Greek cross, and he commissioned Donato Bramante as the initial architect. Bramante’s innovative plan set the stage for a monumental structure, but his death in 1514 led to a succession of architectural luminaries who would each contribute to the basilica’s evolving design.
Following Bramante’s passing, Pope Leo X appointed a team of architects, including Raphael, Fra Giovanni Giocondo, and Giuliano da Sangallo, to continue the work. This marked a shift in the design from Bramante’s original Greek cross plan to a Latin cross layout, featuring three aisles separated by imposing pillars. The architectural baton was then passed to Antonio da Sangallo the Elder, Baldassarre Peruzzi, and Andrea Sansovino after Raphael’s death in 1520, each leaving their imprint on the developing basilica.
The construction faced further changes and challenges, including the sack of Rome in 1527. Pope Paul III (1534–49) then appointed Antonio da Sangallo the Younger, who reverted to Bramante’s central plan and even built a dividing wall between the new construction and the still-functioning Old Basilica. A significant turning point arrived with the commission of the aging Michelangelo as chief architect in 1546. Michelangelo, a master sculptor and painter, brought his unparalleled vision and energy to the project. He largely returned to the Greek cross plan and designed the basilica’s iconic dome, a feat of engineering and artistic brilliance. By the time of Michelangelo’s death in 1564, the drum of the dome was nearing completion.
Michelangelo’s successors, Pirro Ligorio and Giacomo da Vignola, continued his work. Under Pope Gregory XIII (1572–85), Giacomo della Porta took charge, and the dome, with modifications from Michelangelo’s original design, was finally completed under the insistence of Pope Sixtus V (1585–90). Pope Gregory XIV (1590–91) then ordered the construction of the lantern atop the dome. Pope Clement VIII (1592–1605) oversaw the demolition of the apse of Old St. Peter’s and the erection of the new high altar.
The final phase of construction saw Pope Paul V (1605–21) embrace Carlo Maderno’s plan, which extended the basilica into its present Latin cross shape by lengthening the nave eastward. This extension resulted in the basilica reaching its impressive length of 615 feet (187 meters). Maderno also designed the facade and added bays for campaniles. While Maderno designed campaniles, only one was built, and even that was later redesigned by Gian Lorenzo Bernini in 1637.
Although the main structure of St. Peter’s Basilica was completed in 1615 under Pope Paul V, the work continued with embellishments and additions. Gian Lorenzo Bernini, under Pope Alexander VII (1655–67), designed the expansive elliptical piazza that precedes the basilica, creating the iconic St. Peter’s Square. Bernini also contributed significantly to the interior, designing the baldachin over the main altar and niches for important relics.
In conclusion, pinpointing “when was St Peter Basilica built” leads us to understand a protracted construction period. While the cornerstone was laid in 1506, marking the formal commencement, the basilica was essentially completed in 1615. However, considering the ongoing artistic and architectural enhancements, particularly Bernini’s contributions to the square and interior, the legacy of construction extends even further into the 17th century. St. Peter’s Basilica stands not as a building erected in a few years, but as a testament to the sustained vision, dedication, and artistic genius of generations, making it a truly timeless masterpiece.
