It was originally dedicated to Saint Lawrence, and served as the pope's private oratory until the Renaissance.
[2] It formed part of the Lateran Palace, headquarters of the public offices of the papal court throughout the Middle Ages.
Over the course of time, other relics were added, including the cloisonné enameled cross commissioned by Paschal I (Pope from 817 to 824).
The chapel also houses the Uronica or Acheiropoieta Lateranese icon of Christ Pantocrator, known as the Veronica, that was supposedly begun by Saint Luke and finished as an acheiropoieta (which translates to "images not made by human hands") since finished by an angel.
[8][9] Other acheiropoieta include the image of Christ’s face that miraculously imprinted itself on the sudarium of Veronica.