The director of the museum in the Puglia city of Ostuni announced he was resigning on Wednesday after being at the centre of political storm over a controversial social-media post about Premier Giorgia Meloni.
Luca Dell'Atti posted a photo of Meloni upside down on his Instagram profile.
The post was interpreted as a reference to the death of Benito Mussolini, who was hung upside down in Milan's Piazzale Loreto square on April 29, 1945, along with his mistress, Claretta Petacci, and other high-ranking Fascists, after they were shot by partisans.
Luca Dell'Atti apologized soon after, but Meloni's right-wing Brothers of Italy (FdI) party continued to demand his removal anyway and Mayor Angelo Pomes said he was evaluating his position.