The first church on the site, a crude wooden building, went up in 1718. A brick and timber church was completed in 1727. The Great New Orleans Fire destroyed it on Good Friday, March 21, 1788.
The third church was begun in 1789 and finished in 1794, and the church became a cathedral in 1793. The present building dates mostly to 1850. A central tower designed by Benjamin Henry Latrobe in 1819 collapsed in 1850 during rebuilding.
Pope Paul VI named it a minor basilica in 1964. Wikipedia calls it "the oldest cathedral in continuous use in the United States," a title it shares with the Royal Presidio Chapel in Monterey, California.