The present cathedral was built between 1577 and 1593 and is attributed to Italian architect Giacomo della Porta. It was built to replace the former Cathedral of Saint-Croix, destroyed in 1553 in order to make room for developments in the city's defenses, as stated in the permit required by the Council of Ancients in 1559 to the Senate of Genoa and Pope Gregory XIII in order to build a new cathedral. The final stone was laid in 1593 by Jules Guistiniani, made bishop by Pope Sixtus V. It is where Napoleon Bonaparte was baptised on 21 July 1771 and he recited the following on his deathbed in Saint Helena in 1821: "If they forbid my corpse, as they have forbidden my body, deny me a small piece of land in which to be buried, I wish to be buried with my ancestors in Ajaccio Cathedral in Corsica." The cathedral has been a monument historique since 30 October 1906. According to legend, on 15 August 1769, Letizia Buonaparte felt sudden labour pains while in the cathedral. She rushed home to the Buonaparte's home, just steps away, and gave birth to Napoleon on a first floor sofa before she could reach her bedroom upstairs.
The present cathedral is smaller than its predecessor. The interior's Latin cross is delineated by the shallow and modestly-sized transept, which is covered by a dome. The central nave is very high and wide itself, but is short in length compared to the rest of the building. It is covered with barrel vault arches reminiscent of the Renaissance era. The building also has two aisles that depart from the front door and go up to the transept, separated in the middle by the seven chapels beside two rows of three columns. Entering on the right is the marblebaptismal font. It is a simple bowl engraved with Giustiniani's coat of arms, surmounted by a Tuscan bronze crown, below which there is a gold inscription, Heic baptisatus Magnus Imperator. The altar is in polychrome marbles, a gift from Elisa Bonaparte, Napoleon's sister, and has an altarpiece composed of four twisted columns of black marble from Porto Venere. The Corinthian orders have a double pedestal with a collection of marble. The tabernacle dates from the time of the construction of the cathedral and originally stood at the baptismal font. It was then placed at the high altar and stands out for its unorthodox style. Ajaccio Cathedral has seven side chapels, but the following three are the most prominent:
