He became Pope at nineteen with no training, no calling, and no one left alive to tell him no. Then he turned the Vatican into a brothel. His name was Pope John XII. And his nine-year reign proves that giving absolute power to a teenager who doesn't want it is exactly as catastrophic as it sounds. Rome, 937. Octavianus was born into one of the most powerful families in Rome during the worst possible era for papal leadership. The tenth century was not a good time to be pope. The period known as the Saeculum Obscurum—the Dark Age—ran roughly from 904 to 964 and produced a succession of popes installed, controlled, strangled, suffocated, or disposed of by Rome's ruling noble families with the regularity of a corporate management shuffle. Octavianus's grandmother was Marozia, one of the most powerful women in tenth-century Rome. She had been the mistress of one pope, the mother of another, and wielded enough influence over the papacy that her era was called the pornocracy—the rule of the harlots. His father was Alberic II, who ruled Rome as a secular strongman for two decades and had married his own stepsister—Octavianus's mother. Scandal was the family environment before he drew his first breath. Alberic ruled Rome adequately in the rough-edged sense that things mostly functioned and the city did not collapse entirely. In 954, as he lay dying, he made a decision that would echo through Church history. He had his son brought to him. He assembled Rome's leading nobles and clergy at the tomb of Saint Peter. And he made them swear an oath over the apostle's bones: when the current pope died, they would elect Octavianus as his successor. They swore. The following year, the pope died. They kept their word. Octavianus was somewhere between eighteen and twenty-five years old when he became Pope John XII in December 955. He was the second pope in history to take a regnal name. He had received essentially no clerical training. He had shown no particular interest in spiritual matters. He was a Roman aristocrat's son who had grown up in a world of horses, hunting, weapons, gambling, and the pursuit of pleasure. The papacy did not change any of that. What it gave him was money, power, and the removal of the one person who might have reined him in—since his father was already dead. The Lateran Palace, the traditional residence of the popes, became under John XII something that contemporaries did not describe in complimentary terms. Contemporary chronicles describe the palace as effectively a brothel. John kept multiple mistresses openly, including women from Rome's own aristocratic families and, in one account, women who had previously been his father's companions. He hunted obsessively. He gambled extensively and reportedly invoked pagan gods and toasted the devil during dice games. Which must have been jarring behavior from the Vicar of Christ, even by tenth-century standards. He sold church offices—the sin of simony—to fund his spending. He ordained a ten-year-old as a bishop. He once ordained a deacon in a stable. He refused to make the sign of the cross. Now, these accusations come almost entirely from hostile sources. That caveat matters. The synod that formally charged him in 963 was convened by his political enemy, the Holy Roman Emperor Otto I. The testimony against him was produced in a political context that made neutrality impossible. Whether every detail is accurate, exaggerated, or invented is impossible to determine. But what is harder to dismiss is the broader picture that emerges from multiple sources, including some that had no particular axe to grind: this was a young man with no vocation, no training, no interest in the spiritual dimensions of the office he held. And unlimited access to the resources of one of the most powerful institutions in Europe. The one area where John showed something approaching competence was in recognizing military and political danger. Around 960 he personally led an army against the Lombard duchies to the south in an attempt to secure papal territory. He failed to achieve his objectives. He found himself in need of a more powerful protector. He turned to Otto I of Germany, a formidable military and political leader who had been consolidating power across the German territories and had his eye on the imperial title. The arrangement made a certain sense for both men. John needed military protection. Otto wanted to be crowned Holy Roman Emperor by the pope—the only authority with the spiritual legitimacy to confer that title in the eyes of Christian Europe. On February 2, 962, in Saint Peter's Basilica, John XII crowned Otto I and his wife Adelaide as Holy Roman Emperor and Empress. In exchange, Otto guaranteed the independence and territorial integrity of the Papal States. It was a transaction that neither man fully intended to honor. The Holy Roman Empire that John casually restored as a matter of political convenience that morning would last, in various forms, for another 850 years, finally dissolved by Napoleon in 1805. Otto left Rome in March 962 to deal with Berengar, his Italian rival. Before leaving, he lectured John, by this point around twenty-four years old, about his lifestyle and suggested he might consider some reform. John ignored this entirely. He then began conducting secret negotiations with Otto's enemies, including Berengar's son Adalbert and the Byzantine Empire. Apparently worried that Otto's protection would shade into domination. Otto's agents intercepted the correspondence. Otto returned to Rome. John fled to the mountains of Campania, taking the papal treasury with him. Otto convened a synod at Saint Peter's in November 963 at which John was formally accused of a list of offenses that reads, even accounting for the hostile source, like the charges against a man who had treated the papacy as a personal entertainment fund for nine years. The accusations included: sleeping with his father's widow, with a widow he kept as a regular mistress, with various other women by name; blinding his confessor; castrating and killing a cardinal; invoking the devil while gambling; carrying on generally in ways incompatible with the papal office. John was ordered to appear before the synod and answer the charges. He responded by threatening to excommunicate everyone present. The synod deposed him on December 4, 963, and elected a Roman lay official named Leo VIII as his successor. John returned to Rome after Otto left in early 964 and retook the city. He convened his own synod. He declared his deposition uncanonical. He set about punishing his enemies with systematic thoroughness. Some were mutilated. Some fled. Leo VIII escaped to Otto, who was preparing to return to Rome and deal with the situation personally. He did not get the chance. On May 14, 964, John XII died suddenly at the age of twenty-seven. The circumstances of his death, as reported by Liudprand of Cremona and others, were consistent with the rest of his life. One account says he suffered a fatal stroke in the middle of an adulterous encounter with a married woman. Another says the woman's husband arrived unexpectedly, found the pope in his wife's bed, and threw him out of a high window. A third account has the husband simply beating him to death. None of these accounts can be verified. All of them are consistent with what his contemporaries thought of him. Which says something about the reputation he had built. He was buried at the Lateran. His pontificate ended the period of the Saeculum Obscurum. The reform movement that followed, partly motivated by sheer embarrassment at what the papacy had become under John and his predecessors, eventually produced the Gregorian reforms of the eleventh century. These reforms restructured the relationship between the Church and secular power and established new standards for clerical conduct. The papacy that emerged from that process was considerably different from the one John had inherited and run as a private party. Here's what makes Pope John XII more interesting than just a scandal. He wasn't unique in tenth-century Rome. Popes before him had been installed by noble families, controlled by powerful women, strangled by political enemies, and disposed of with barely a second thought. What made John different was this: he was the first pope in that era of chaos who was chosen entirely through a legal process, by an oath sworn over Saint Peter's bones, by his own father's deathbed decree. He wasn't imposed by violence. He wasn't installed by coup. He was chosen and given power by the explicit will of Rome's most powerful family. And he immediately revealed what happens when you give absolute power to a teenager who doesn't want it and has nobody left alive to tell him no. He didn't become corrupt because the position corrupted him. He was already who he was—a young man interested in hunting, gambling, women, and pleasure. The papacy simply gave him the resources to pursue those interests without limits. He didn't become evil. He just became completely, utterly himself, with the resources of the Church to fund it. That's actually more revealing than if he'd been a secret monster hiding under a respectable exterior. He was transparent about what he was. The contemporary chronicles complaining about his mistresses and gambling and devil-toasting weren't describing a hypocrite. They were describing a young man who saw no reason to pretend to be something he wasn't. Which is perhaps the most dangerous thing a person in absolute power can be: completely honest about not caring. He died at twenty-seven, probably in a manner consistent with how he lived—either stroke during an affair, thrown from a window by a husband, or beaten to death. We'll never know. All three accounts fit perfectly. What we do know is this: his nine-year disaster—a teenager with no training, no calling, and no one to tell him no, given absolute power over one of the world's richest institutions—triggered a reform movement that transformed the Church. The Gregorian reforms that followed his reign lasted centuries. They restructured how the Church related to secular power. They established standards for clerical conduct. They rebuilt the papal office into something that wasn't just a political toy for Roman families. Which means Pope John XII accomplished something without even trying: he made the Church so embarrassed by what he had done that it forced itself to become better. He was too young, too unprepared, too uninterested, and too unconstrained to be anything but a disaster. And his disaster became the catalyst for nine centuries of reform. Sometimes the worst outcomes produce the most consequential changes. Sometimes a teenager with absolute power, doing exactly what he wants because nobody left alive can tell him no, becomes the reason an entire institution has to fundamentally rebuild itself. Sometimes history turns on the axis of a completely terrible pope who toasted the devil while gambling and ordained ten-year-olds as bishops. Sometimes the most consequential thing you can do is be such a comprehensive disaster that your institution can't ignore the problem anymore.