It doesn’t appear that the Catholic Church has an official policy regarding whether or not a pope’s remains should be embalmed. However, we do have some clues, if information about more modern papal funerals is anything to go by. According to Slate, a number of recent popes have been fully embalmed after their deaths, including all of the four popes preceding John Paul II. The full embalming process requires removing nearly all blood and other bodily fluids from the remains, replacing them with a preservative-heavy solution that also contains dye meant to give the body a more lifelike appearance.

In contrast to earlier tradition, John Paul II appears to have not been fully embalmed. According to the Vatican, his body was only “prepared” for a public viewing. This vague statement leaves a fair amount of room for interpretation, but it’s likely that the pope’s body was given some sort of treatment with preservatives to keep it in a presentable (that is, not visibly decomposing) state.

After all, Pope John Paul II died in 2005, well into an era where reporters and news cameras could broadcast any issues spotted during the public viewing, while thousands of people were filing past his remains. While some reported telltale signs of deterioration, it appears that whatever the light treatment that was applied to Pope John Paul II’s remains, it worked far better than for other popes who experienced similar preparations.

Though much is made of the ancient and storied traditions that are part of life in the Vatican, things can and indeed do change. Sometimes, those changes are sweeping, even monumental, like those enacted by the Second Vatican Council in the 1960s. Per Britannica, Vatican II, as it’s often called, loosened rules for some religious order members and allowed for mass to be held in numerous local languages and not just Latin. It was also, of course, fairly controversial and led some conservative members of the church to complain well into the present day.

Then again, sometimes the changes to tradition are seemingly small, though they can have big consequences later. Take Pope Pius X, who died in 1914. According to the L.A. Times, he refused to allow embalmers to remove his internal organs and preserve them in separate jars. It was by then a pretty well-established practice that had been enacted in the wake of previous popes’ deaths.

But Pius X thought this all was nothing short of grotesque and his successors seemed to agree. Yet, where the remains of Pius X seem to have suffered no great damage from this new tradition, other popes’ bodies — with quickly deteriorating organs still intact inside them — would not be quite so fortunate.

While there’s plenty to shake one’s head at when it comes to relic hunting and experimental embalming, those mishaps can’t measure up to the infamous Cadaver Synod. It essentially began in 897 CE, when Pope Stephen VI decided that his predecessor, Pope Formosus, had committed a great sin (or had proven to be politically inconvenient to Stephen’s way of doing things). According to Atlas Obscura, Formosus had once been a pretty powerful bishop. Pope John VIII got so nervous that he had Formosus excommunicated. John was eventually killed and his successor reinstated Formosus, who managed to snag his own spot as pontiff for five years before dying. By this time, the papal throne had a pretty high turnover rate, and anyone sitting there was bound to feel pretty nervous.

So, Stephen VI held a trial for Formosus, whom he believed had broken some key rules when he became pope. Stephen had his predecessor’s remains exhumed, dressed in liturgical robes, placed in a chair, and put on trial.

Being dead, Formosus was not really able to defend himself against the charges and was quickly found guilty. National Geographic reports that his remains were unceremoniously tossed in Rome’s Tiber River, where a fisherman pulled the body out of the water. Formosus’ remains were soon linked to rumors of miracles. Stephen was unsurprisingly felled by an uprising and the body of Formosus was reinstalled in a tomb beneath St. Peter’s Basilica.

Pope Paul VI’s remains were only “lightly embalmed” after his 1978 death, according to the Los Angeles Times. While that seemed to have worked out decently enough for one of Paul’s successors, John Paul II, the reality of the 1978 funeral was quite a bit more gruesome. Part of the issue may have been with not only the manner in which the deceased pontiff’s body was treated, but with the environmental conditions in the midst of what seems to have been a hot and humid summer.

The combined effects of the lack of embalming and the summer weather were unfortunate for Paul VI and his mourners, to say the least. Reportedly, a number of fans were installed around the pope’s remains as they lay in state inside St. Peter’s Basilica. It was done in order to somehow redirect the stench during the public viewing, according to Ozy.

Meanwhile, The Washington Post reported that, though then-First Lady Rosalynn Carter spoke glowingly of the pontiff’s spiritual life, some couldn’t help but notice that the pope’s body had turned an alarming green-gray color. The Vatican declined to say just what had or had not been done to Paul VI’s remains in the immediate aftermath of his death, but it was clear that it hadn’t been enough to stand up to the rigors of a summertime memorial.