Quick Answer
No pope has ever been officially executed or put to death during their papacy. There have been a few popes who likely died from poisoning or were killed under mysterious circumstances, but none have been definitively executed while serving as pope.
Brief History of the Papacy
The papacy has existed for nearly 2,000 years, since the time of St. Peter who is considered the first pope. He was followed by a long line of popes leading up to the current Pope Francis. Over this time, the papacy has evolved from a position with little power and influence to one of great authority both within the Church and at times in the secular world.
While most popes have lived out their reigns peacefully, there have been periods of great turmoil and violence surrounding the papacy. The Middle Ages in particular saw many power struggles between popes and secular rulers like kings and emperors. Assassinations, military sieges, arrests, and exile were not uncommon fates for popes caught up in these conflicts.
Yet despite the volatility that has surrounded the papacy at different points in history, no pope is known to have been officially put to death for religious or political reasons while serving as pope. There are a few questionable cases we will examine, but the fact remains that no execution of a pope during his reign is conclusively documented.
Suspicious Papal Deaths
While no pope has been outright executed, assassination by poison has long been suspected in the deaths of several popes throughout history. Poison would have been a convenient way for the papacy’s enemies to remove a troublesome pope without publicly executing him. Here are a few of the suspicious papal deaths over the centuries:
Pope John VIII (872-882)
Pope John VIII’s reign occurred during a time when the papacy was caught between alliances with competing Italian rulers and eventually the Holy Roman emperor. John made plenty of political enemies including among the powerful Frankish bishops. In 882, John suddenly died after being poisoned along with several members of his staff.
Pope Leo VIII (963-965)
Leo VIII was installed as an “antipope” against the rightful Pope Benedict V due to political machinations. Leo is believed to have ordered Benedict poisoned shortly after taking power. Benedict eventually died in 965, though it is unclear if poisoning was the cause. Leo himself died within months under suspicious circumstances.
Pope Clement II (1046-1047)
Clement II was installed by Emperor Henry III and immediately crowned Henry as Holy Roman Emperor. After just 10 months as pope, Clement died suddenly, with rumors circulating that he had been poisoned for acting against Henry’s wishes in church affairs.
Pope Alexander VI (1492-1503)
The infamous Renaissance era Pope Alexander VI was accused of poisoning political enemies as well as cardinals who opposed him. He ultimately died himself after consuming poisoned wine intended for someone else.
Pope Paul III (1534-1549)
Paul III was known as a very authoritarian pope who consolidated church power. His sudden death led to rumors he had been poisoned, perhaps by a dissatisfied member of his own family.
So while assassination by poison was not uncommon in the papal court over the centuries, no pope appears to have been officially sentenced and executed for religious crimes. Poisoning allowed papal enemies to remove troublesome popes covertly without public executions.
Executions of Former Popes
There are a few instances of former popes later being executed after they were deposed from the papacy:
Pope Formosus (891-896)
Formosus had a tumultuous pontificate, being tried for treason and other charges before dying in 896. His corpse was later exhumed, put on trial, and thrown into the Tiber River by his angry successor Stephen VI in the “Cadaver Synod” trial. This grotesque mistreatment of his remains is the closest a pope came to execution.
Pope Sergius III (904-911)
Sergius III took power with the help of an antipope and was accused of ordering the murders of his papal predecessors Leo V and Christopher. Years after his own death, his remains were dug up and burned in 945.
Antipope John XVI (997-998)
John XVI seized Rome and installed himself as pope, but was later arrested, mutilated, and likely murdered in a German prison around 1001. As an “antipope” he is not officially recognized as a valid pope.
So while controversial popes were sometimes subjected to post-mortem executions and outrages, none were officially executed during their recognized pontificates.
Attempted Executions of Popes
While no pope has ever been lawfully executed, there have been failed attempts to capture and kill sitting popes over the centuries:
Pope Leo IX (1049-1054)
Holy Roman Emperor Henry III sought to arrest or execute Leo IX after the pope threatened to excommunicate him. Henry’s soldiers attacked Leo’s entourage at the Battle of Civitate but lost the engagement, saving Leo from potential imprisonment or execution.
Pope Paschal II (1099-1118)
Holy Roman Emperor Henry V took Pope Paschal II prisoner along with many cardinals and bishops. Henry threatened to execute Paschal unless he agreed to crown Henry as emperor. Paschal reluctantly took this oath of submission but later refused to honor it.
Pope Boniface VIII (1294-1303)
The French King Philip IV sent a mercenary named Nogaret with orders to arrest Boniface VIII and bring the pope before a council. Nogaret and his men assaulted the pope’s palace but failed to take him prisoner.
Pope Clement VII (1523-1534)
After allying against the Holy Roman Emperor, Clement VII was nearly captured when imperial troops sacked Rome in 1527. Clement managed to escape to safety in Castel Sant’Angelo and avoided potential execution at Charles V’s orders.
So arrest and execution of a reigning pope has certainly been attempted, though no pope’s enemies ultimately succeeded in carrying it out. The aura of papal authority likely dissuaded executions, even when popes were imprisoned or otherwise mistreated.
Legality of Executing A Pope
While canon law has long protected the pope from heresy trials or deposition, it does not technically prohibit arresting and executing a pope for capital crimes or treason. But the pope is considered a sovereign head of state, so regardless of canon law, arresting or prosecuting a pope would violate international law today.
Canon Law Protections
- As head of the Catholic Church, the pope is protected from prosecution by other clergy by canon law.
- Canon law states “the First See is judged by no one”
- No ecumenical council has authority to depose or judge the pope
So canon law provides considerable protections against arrest, imprisonment, deposition, and execution of a pope by the Church itself.
Secular Authority
However, as a head of state, popes have interacted with secular rulers who often held power of life and death over their subjects. While canon law may prohibit trying a pope in a church setting, secular leaders like kings and emperors have asserted authority at times to potentially arrest and execute a pope for crimes against the state or treason.
International Law
Today, the pope is protected under international law both as head of a sovereign nation-state (Vatican City) and head of the Holy See. So attempting to arrest or prosecute the pope would violate numerous international laws against detaining diplomatic officials and heads of state.
Conclusion
While popes have held an aura of spiritual authority and protection over the centuries, they were not completely immune from deposition, arrest, or even possible execution under certain scenarios. But even when popes were killed, it was typically done through covert poisoning rather than any official or lawful sentence of execution.
No pope has ever been lawfully put on trial and executed for crimes against the faith or treason during their recognized pontificate. There have been failed attempts at arresting various popes and several suspicious deaths, but no execution ordered by a church council or secular authority is conclusively documented in history. So while theoretically possible under certain conditions in previous eras, no pope has ever definitively undergone an official execution.
