Pope Stephen III
The founder of the chapel is unknown. It was originally dedicated to Saint Lawrence, and served as the pope's private oratory until the Renaissance. It is located at the top of the Scala Sancta, ("Holy Stairs"). The first mention of the chapel is found in the "Liber Pontificalis", during the tenure of Pope Stephen III (†772). The antiquarian Marangoni along with Onofrio Panvino quote documents that cite the acquisition in 583 by Pope Gregory of relics from Constantinople, including an arm of St Lawrence, that were housed in the church of St Lawrence in Lateran palace.