When thinking about the most harmful groups in human history, some groups come to mind right away. Oil companies that knowingly poisoned people with leaded gasoline, which lowered IQ levels around the world by several points. Central banks that messed with economies and ruined countries' finances. Defense industry lobbyists who made money off of endless wars and the deaths of hundreds of thousands of people. But there is one group that stands out: the Roman Catholic Papacy. It has done more harm than all of these other groups put together. This medieval power structure not only ruled Europe for more than a thousand years, but it also set back human civilization by hundreds of years by systematically hiding knowledge, organizing mass violence, and putting in place control systems that still exist in some form today.
The Made-Up Origins of Institutional Christianity
The story starts not with a message from God, but with the need for political change in the falling Roman Empire. In the early centuries of the Common Era, Jews living under Roman rule hoped more and more that a messianic figure would come and free them from the oppression of pagans. This rich land gave rise to many charismatic prophets and teachers, such as Theudas, who urged people to rise up against Rome; Apollonius of Tyana, who shared ancient wisdom; John the Baptist, who shared Essene teachings; and many others whose stories and sayings would later be combined into composite narratives.
The revolutionary movement that pushed for monotheism, human equality, and justice spread quickly among the poor, slaves, and Jews, who were all oppressed. This made society unstable and put Roman power at risk. By the early 4th century, Emperor Constantine was in trouble. The empire was falling apart because of religious unrest inside and military pressure from outside.
Constantine's answer was very clever and cynical. Instead of continuing to go after this growing movement, he would take it over and control it. The Edict of Milan in 313 CE ended the persecution of Christians, and the Council of Nicaea in 325 CE set up the religion's rules. Constantine himself called this council to the imperial palace to settle disagreements about doctrine, especially the Arian debate about the nature of Christ.
The important choice made at Nicaea turned a wide range of teachings into a tool for control. The council made an unassailable theological position by saying that Christ was not just a prophet or messenger, but God himself. If Jesus was God incarnate, then no future prophet could claim equal authority. This new idea in theology was exactly what Constantine needed for his political goals. It strengthened religious authority and made sure that no one could challenge that authority in the future.
The institutional framework established to govern this nascent state religion-subsequently known as the Papacy-developed into a parallel power structure to the empire itself. It is very important to tell the difference between the Papacy (the religious organization that runs the church) and Vatican City (the physical area in Rome where the papacy is based). The Papacy had a lot of power over both spiritual and temporal life in Europe. In the end, it had more power than kings and emperors.
The Rise of the Papacy: Surviving the Fall of the Empire
The Western Roman Empire fell apart in 476 CE, which should have ended the new papal institution. Instead, it saved the Papacy. Church leaders had planned to make themselves separate from Roman political power by providing social services and keeping in touch with even Rome's enemies. When barbarian invasions destroyed the structures of the empire, the Church's infrastructure stayed the same.
In 452 CE, Pope Leo I met Attila the Hun and convinced him not to destroy Rome. This was a turning point in history. This meeting is often seen as a diplomatic victory for the pope, but it was actually one of the biggest missed opportunities in history. If Attila had destroyed the papal institution along with other Roman buildings, centuries of oppression might have been avoided.
The Papacy quickly filled the power vacuum left by the fall of Rome. The institution spread across Europe like ivy, wrapping the whole continent in a religious network. In 754 CE, Frankish King Pippin gave a lot of land to the Pope, making the change from religious organization to sovereign state official. After that, the Papacy helped bring back the Holy Roman Empire, making itself the hidden power behind this new political structure.
The Dark Ages: Controlling Knowledge and People
The time between the fall of Rome and the conquest of Constantinople in 1453, which lasted about 1,100 years, is known as the Middle Ages. It was called the "Dark Ages" because of the policies of the pope. Trade was hurt by the breakdown of Roman road networks. The constant fighting burned libraries and sent scholars all over the place. The Papacy stepped in and became the only source of stability and authority in this mess.
The Church used ignorance as a weapon. By keeping the Bible only in Latin, a language that most people couldn't understand, clergy made it impossible for anyone else to interpret the Bible. Priests claimed to be important middlemen between God and people, which made them very rich and powerful. Selling indulgences, which literally meant selling spots in heaven or less time in purgatory, became a huge source of income.
The system of indulgences turned into complicated ways to make money. The Church knew exactly how much time each indulgence would take away from purgatory. Rich people could buy salvation not just for themselves, but also for family members who had already died and were suffering in the afterlife. Professional "pardoners" went from town to town, scaring people with vivid descriptions of hell and offering a way out for the right price. This practice became so corrupt and profitable that it led to the Protestant Reformation when Martin Luther nailed his Ninety-Five Theses to the church door in 1517.
People who weren't rich had to pay a lot of taxes on top of indulgences. Tithes took up a lot of the harvests. Rich people gave gold and land. If you didn't follow the rules, you were threatened with excommunication, which meant being kicked out of the Church and damned in the afterlife. Even very religious people like Hildegard of Bingen were punished for disagreeing with church leaders.
The Albigensian Crusade and Inquisition: Crushing Dissent
The response was brutal when other Christian groups started to question the pope's authority. The Cathars of southern France had a dualistic theology that mixed Gnosticism with Christian ideas. They believed in a cosmic battle between good and evil and accepted reincarnation. Pierre Waldo, a rich Frenchman, started the Waldensians. They committed the "heresy" of translating the Bible into common French so that regular people could read it themselves.
Pope Innocent III's response to these movements set a terrible example: crusades were started not against Muslims but against other Christians. Southern France was badly hurt by the Albigensian Crusade (1209โ1229). When crusaders asked how to tell Catholics from Cathars in Bรฉziers in 1209, papal legate Arnaud Amalric is said to have said, "Kill them all! God will know his own."
About 20,000 people died in the massacre that followed. These included men, women, children, and even priests who were hiding in churches. The letter from the crusader army to the Pope didn't say they were sorry; it just said they were happy that God had punished them. This pattern of total slaughter happened all over the region as towns gave up without a fight after hearing what happened to Bรฉziers.
The Albigensian Crusade led to the Medieval Inquisition, which is probably the most unfair court system in history. Inquisitorial courts held secret trials where the accused could not face their accusers or mount a strong defense. These courts were run by judges and prosecutors chosen by the Church. Confessions could be gotten by torture, which was not only allowed but also encouraged.
The Inquisition had power all over Europe and went after anyone who read books that weren't approved, did scientific research, or tried to translate the Bible. The Church thought that heretics had to go through hell on Earth before going to hell for all time. This usually meant being burned at the stake.
The Crusades: A Holy War and a Mass Murder
People were shocked by the Papacy's holy wars against Muslims in the Middle East, but crusades against European heretics are better known. These campaigns lasted about 200 years and caused the deaths of about 3 million people, including civilians and massacre victims.
The capture of Jerusalem on July 15, 1099, during the First Crusade, is an example of how cruel it was. After breaking through the walls of the city, the crusaders killed so many people that even Muslim historians were shocked. Accounts from the time say that blood was running knee-deep in the streets, and both defenders and civilians were killed without regard for their lives. Modern estimates say that between 3,000 and 40,000 people died right away after the event.
Raymond of Aguilers, a chronicler of the Crusades, wrote without shame, "When we took Jerusalem, a great massacre began in the city... This victory was seen as a blessing from God. There was so much blood in the temple that the crosses were up to their horses' knees." The systematic killing included all Muslims and Jews, with only a few being spared by paying ransom.
These wars were not just fights over religion; they were also ways for the pope to gain political power. Participants received plenary indulgences, which meant that all of their sins were forgiven. This made crusading a way to get to heaven and also gave the Church a lot of money from the war. The Papacy used crusades as weapons against anyone they thought was an enemy, which made the idea less valuable over time.
The Plague: When the Pope's Order Brought Death
Pope Gregory IX's 1232 announcement about cats may have been the most deadly thing a pope ever did. The bull Vox in Rama talked about a heretical group that worshipped a statue of a black cat that stood for Satan. The document did not directly mandate the extermination of cats; however, it linked cats-especially black ones-to demonic entities.
The outcome was predictable: over the next hundred years, cats were systematically killed all over Catholic Europe. It is thought that millions of cats were killed. There is still debate about whether Gregory meant to kill a lot of cats, but the results were terrible.
In 1347, ships coming to Messina, Sicily from the Black Sea brought not only goods for trade but also rats infected with Yersinia pestis, the bacterium that causes bubonic plague. Cats would usually keep the number of rats down on ships and in port cities. But after a hundred years of killing cats, the number of rats grew out of control.
The Black Death spread across Europe at an awful speed. About 50 million people died in six years, which is about one-third of Europe's population. In some areas, as many as 60% of people died. The social and economic destruction almost brought an end to European civilization.
The Church's response to the plague, which it had indirectly caused, made the situation worse. Instead of admitting that there was a link between the plague and the killing of cats, the Pope said that the plague was God's punishment for not being pious enough and not going to church enough. The recommended course of action: increased prayer, additional donations, and the veneration of holy relics through touch and kiss.
These habits made it easier for diseases to spread. Sick people packed into churches, spreading the disease. The Church said that God's will was not for people to be quarantined or get medical care. People blamed Jewish communities for poisoning wells, which led to pogroms and mass killings. The institution that had set the stage for the pandemic used it to gain more power and get rid of people they thought were enemies.
Resistance in the Renaissance: Science vs. Dogma
The plague's destruction, strangely enough, made the pope's power weaker. With so many people dead and the Church's solutions not working, survivors started to doubt the Church's infallibility. This crisis of faith led to the Renaissance, as people looked for a rational way to understand things instead of religious dogma.
The Papacy, however, fought hard against the rise of intelligence. The Church quickly banned Nicolaus Copernicus's book On the Revolutions of the Celestial Spheres after he suggested a heliocentric universe model, which said that the Earth orbited the Sun instead of being in the center of the universe. This theory went against the Bible's view of the universe and humanity's special place in creation, which threatened the Church's authority at its core.
The fate of Galileo Galilei showed what could happen to someone who does scientific research. In the early 1600s, Galileo used better telescopes to confirm Copernican heliocentric theory by looking at the stars. In 1633, the Inquisition arrested him and questioned him, threatening to torture him. He was 70 years old at the time.
The outcome of the trial was set in stone. People thought Galileo was "vehemently suspect of heresy" because he thought the Sun was in the middle of the universe. Galileo had to publicly take back what he had said about science and "abjure, curse, and detest" heliocentrism. He spent the rest of his life under house arrest until he died in 1642. His published works were prohibited, encompassing any subsequent writings.
Giordano Bruno had an even worse fate because he said that the universe went on forever and that there were many worlds that could support life. Bruno was arrested in 1593 and spent seven years in jail being questioned by Cardinal Bellarmine, the same inquisitor who would later go after Galileo.
Bruno refused to give up his philosophical and cosmological beliefs, even when he had the chance to do so. He was burned alive in Rome's Campo de' Fiori on February 17, 1600. Witnesses say that when Bruno was offered a crucifix, he defiantly turned his head away. His ashes were thrown into the Tiber River, and all of his works were put on the Index of Prohibited Books.
Witch Hunts: Institutionalized Killing of Women
The persecution of women as "witches" exemplifies one of history's most systematic campaigns of gender-based violence. Pope Innocent VIII wrote the bull Summis Desiderantes Affectibus in 1484 to make Church policy against witchcraft official. This order started witch hunts that would kill more than 100,000 people over the next three hundred years.
The trial methods were meant to make sure that everyone was found guilty, even if they were innocent. In the water test, the accused woman was tied up and thrown into water. If she floated, this "proved" that demons were helping her, and she was burned. If she sank and drowned, her innocence was recognized after her death. The fever test involved burning the person with hot iron. If the person healed slowly, it meant they were a witch; if they healed normally, it was rare for such bad burns.
It was common to torture people. Women were tortured with stretching racks, crushing stones, lack of sleep for up to 40 hours, and other tools of torture until they either confessed (and were killed) or died from the torture itself. Most of them confessed to end their pain, even though they were innocent.
Most witch accusations had nothing to do with real witchcraft. People who wanted to steal land would accuse families of witchcraft, which led to execution and the loss of their property. Women had personal problems that led to deadly accusations. Most insidiously, educated women-especially teachers and healers in rural villages who didn't follow Church rules-were specifically targeted for death.
The witch hunts had two main goals: to get rid of women who thought for themselves and might question male authority, and to strengthen the Church's power through fear-based displays. By calling women's independence and knowledge demonic, the institution made sure that women stayed in the dark and under control for generations.
Modern Scandals: The Church's Ongoing Crimes
Some people might say that the abuses of the Middle Ages were just things that happened at the time, but the Catholic Church is still sexually abusing children today. It is hard to understand how big this ongoing scandal is.
A report from 2004 said that between 1950 and 2002, at least 4,392 priests sexually abused 10,667 children in the United States. These are just the cases that were reported. The Royal Commission in Australia found 4,444 cases of child abuse between 1980 and 2015. During this time, seven percent of Australian Catholic priests were accused of abuse. In some dioceses, more than 15% of priests were found to be guilty.
The 2021 report from France showed shocking numbers: between 1950 and 2020, more than 3,000 priests and Church workers sexually abused an estimated 216,000 children. The same things happened in many other countries, like Germany, Poland, Ireland, and many more. The total number of child victims around the world is probably more than one million, including unofficial reports.
The response from institutions has always been the same: protect the people who did it, keep the victims quiet, and avoid legal responsibility. Instead of being reported to the police, abusive priests were often moved to new parishes where they could keep doing bad things. John Paul II, Benedict XVI, and Francis all apologized many times, but there has not been any real structural change.
The Church has paid billions of dollars to settle lawsuits with victims, but it still puts its image ahead of the safety of children. This ongoing crisis is the most recent example of a pattern that has been going on for a thousand years: an institution claiming moral authority while allowing or committing terrible abuses.
The Reckoning: The Price of Civilization
It is hard to fully measure the damage that the Papacy has done to Europe over the years. For hundreds of years, the church kept scientific knowledge from the public by burning books and punishing scholars whose work could have questioned the church's authority. How many medical breakthroughs were put off? How much progress in technology was stopped? What philosophical insights were forfeited when intellectuals were executed by burning?
The Crusades, Inquisition, and witch hunts killed millions while traumatizing entire populations. The Black Death killed 50 million people because the pope persecuted cats. Think about the mental harm as well as the body counts: generations raised in fear, taught that questioning authority would send them to hell forever, and not allowed to read or think for themselves.
The Church's control of wealth made people poor by taxing them all the time. Indulgences and simony ruined the institution from the inside out and took money from the faithful. Nepotism put relatives who weren't qualified in charge. There was a lot of sexual corruption. Many clergy had concubines and had children even though they had promised to stay celibate. Some bishops even charged priests fees to keep these relationships going.
Defenders of the present say that it's not fair to judge historical institutions by today's standards. But the Church's own stated values-love, compassion, truth, and protection of the innocent-make its actions wrong by any standard. An organization that said it spoke for God's will on Earth did horrible things that were both cruel and corrupt.
According to statistics, the power of institutional Christianity is finally fading. People are still going to church less and less in Europe and North America. Every new abuse scandal makes more people leave the church. This institution may eventually lose its hold on human consciousness in a few generations.
The history of the Papacy is a warning about the dangers of giving institutions too much power while pretending to be moral. This kind of power always corrupts, whether it is held by religious groups, governments, or businesses. The legacy of the medieval Church serves as a reminder that the most heinous acts are frequently committed by individuals purporting to uphold the highest ideals; furthermore, contesting such authority, despite its inherent risks, is crucial for human advancement.