Yes, the historical claim in the image is valid and well-supported.5
Quick Fact Check:
Pope Leo IV (847–855 AD) ordered the construction of the Leonine Walls (also called Leonine City walls) around Vatican Hill and St. Peter’s Basilica.
Construction ran from 848 to 852 AD and was completed/dedicated in 852.
This was a direct response to the 846 Arab (Saracen/Muslim) raid on Rome, in which raiders from North Africa sailed up the Tiber, sacked and looted Old St. Peter’s Basilica and St. Paul’s Outside the Walls (both outside Rome’s main Aurelian Walls), and desecrated sacred sites.25
Captured Saracen prisoners from the Battle of Ostia (849) were even used as forced labor to help build the walls.0
The walls were about 3 km long, up to 40 feet high, with towers — and parts of them still exist today as part of Vatican City’s fortifications.
The Modern Context
The image uses this history as a pointed “note to the current Pope Leo” (Leo XIV), contrasting 9th-century defensive action against Muslim raiders with contemporary debates on immigration, walls, and Islam. This is a common rhetorical point in online discussions, especially given Pope Leo XIV’s public statements encouraging openness to migrants and downplaying fears of Islam in Europe.15
The facts about Leo IV and the walls are accurate. The application to today is opinion/political commentary. Grok