By Michael Lewis
IMAGE: Bullae of Leo X found near Calbourne, Isle of Wight (IOW-87E365), which has broken in half; this is not uncommon for bullae to break in half because of a natural weakness where the cord runs down the middle, top to bottom.
Robert Francis Prevost (b. 1955) was elected Pope on Thursday (8 May 2025), taking the ‘papal name’ Leo, said to be after Leo XIII (r. 1878-1903), who was committed to the ‘social teaching of the Church’ in an era of change. Like his thirteen predecessors, the curia under Leo XIV will issue proclamations and edicts with leaden seals (papal bullae).
The design of these bullae has not changed much over time – those of the medieval period have similar designs to those issued today. One side (the reverse) depicts the busts of St Paul and St Peter with the abbreviation of their names (SPA SPE). The obverse gives the name of the Pope. These lead items were then attached (as they are now) to vellum documents with hemp or silk, thus providing the documents with authenticity.
The Portable Antiquities Scheme (PAS) has recorded almost 700 papal bullae, most of which are medieval (1066-1540) in date; four are earlier, and nine are more modern. The AHRC-funded Medieval Ritual Landscape (MeRit) project has studied bullae recorded with the PAS to better understand ‘lived religion’. All recovered from the soil, somehow, many of these objects seem to have come into the possession of everyday people. Various examples show evidence of having been used (presumably in spiritual practices), modified (sometimes into other objects), and/or damaged (probably during the Reformation).
Of the PAS-recorded bullae studied by MeRit, only a small number were issued by popes called Leo. The earliest, a rare early-medieval bulla, found at Denton with Wootton, Kent (KENT-01AD9F), is very likely to have been issued by Leo III (r. 795-816). Two others were issued in the name of Leo X (r. 1513-21), one found near Calbourne, Isle of Wight (IOW-87E365), of which only half survives, and the other at Dunton, Norfolk (NMS-493185).
This year, another bulla of Leo X was found in Norfolk, at Wicklewood (NMS-0D05B2). Bullae of Leo X are interesting because papal bullae are rare so close to the Reformation, when the English Church broke from Rome. Perhaps more intriguing is why popes did not use the name Leo during the High Medieval period, when papal bullae were issued in significant numbers.
Before Leo X, we must return to the 11th century to find another pope named Leo. This Leo, IX (r. 1049-54), was instrumental in the Great Schism of 1054, which resulted in the break between the Catholic Church and the Eastern Orthodox Church. Unsurprisingly, the name Leo was not popular thereafter, next adopted by Giovanni di Lorenzo de’ Medici (of Florence) in 1513 on the eve of the Reformation; he was the last pope not to have been a priest when elected!