5 Times the Medieval Catholic Church Was Weirdly Hardcore

Picture this: it is the year 1139, and a group of bishops in Rome calmly vote to ban one of the deadliest new weapons in Europe. Not for everyone, just for Christians using it on other Christians. The penalty is excommunication. The weapon is the crossbow.

This is the same institution that blesses kings, runs courts, and owns land across the continent. Yet it is also trying to regulate how people kill each other, when they can fight, and what counts as a just war. The medieval Catholic Church was not a simple cartoon villain or haloed hero. It was a massive power structure that could be brutal, idealistic, hypocritical, and surprisingly “based,” depending on where you were standing.

Here are five moments and systems where the Catholic Church did something people today often find unexpectedly hardcore, humane, or just plain strange. Each one shaped how Europe fought, studied, married, and thought about power.

1. Banning the Crossbow (Sort Of): The Church vs. High-Tech Killing

What it was: In 1139, the Second Lateran Council, called by Pope Innocent II, banned the use of crossbows and similar weapons by Christians against other Christians. The penalty was excommunication. The ban did not apply to using them against non-Christians.

The exact wording condemned “that deadly art” of crossbows and archery “against Christians and Catholics.” This is one of the earliest large-scale attempts in Europe to limit certain weapons on moral grounds.

Concrete example: The crossbow had already proven terrifying. At the Battle of Hastings in 1066, Norman forces used archers and possibly early crossbowmen against Anglo-Saxon shield walls. By the 12th century, crossbows could punch through mail armor and let a half-trained peasant threaten a knight who had spent his life training for war.

The Church’s ban came from fear that this cheap, powerful weapon would supercharge the already bloody feuds between Christian lords. It was not a pacifist move. The same Church would bless crusades against Muslims and heretics. But it tried to keep Christian-on-Christian slaughter from turning into an arms race.

Did it work? Not really. By the 13th century, crossbows were standard in many European armies. The ban was widely ignored or quietly forgotten. Later popes employed crossbowmen themselves. The technology was simply too useful.

Why it mattered: The crossbow ban did not stop the weapon. What it did do was set a pattern. The Church claimed the right to regulate weapons and the ethics of war. It was an early form of arms control, even if it was patchy and self-serving.

Modern historians sometimes point to this as a medieval ancestor of later debates about banning chemical weapons, landmines, or nuclear arms. The idea that some weapons are “too cruel” or destabilizing for civilized people to use did not start in Geneva. It has roots in councils like Lateran II.

So what? The crossbow ban showed that the medieval Church was willing to challenge military technology on moral grounds, helping create the long tradition of arguing that not all weapons are acceptable in war.

2. The Peace and Truce of God: Trying to Put Rules on War

What it was: From the late 10th century, bishops in parts of France and later elsewhere launched the Peace of God and the Truce of God movements. These were church-led efforts to limit who could be attacked and when fighting could happen.

The Peace of God tried to protect noncombatants: peasants, clergy, merchants, women, and church property. The Truce of God tried to restrict fighting on certain days, especially Sundays, major feast days, and sometimes whole seasons like Lent.

Concrete example: At the Council of Charroux in 989, bishops in Aquitaine threatened excommunication for anyone who robbed or harmed peasants or church property. Later councils expanded this. By the early 11th century, some areas had rules like “no fighting from Wednesday evening to Monday morning” or during Advent and Lent.

Did knights obey? Sometimes. Sometimes not. Enforcement depended on local power and enthusiasm. But the idea spread. By the 12th century, the concept that war should spare certain groups and times was widely known, even if often violated.

The Peace and Truce of God were not modern human rights. They were as much about protecting Church wealth and stabilizing feudal order as about mercy. Yet they did something new: they turned random private warfare into something that at least claimed to have rules.

Why it mattered: These movements helped create the habit of thinking that war could be judged morally. They fed into the later “just war” tradition, where theologians like Thomas Aquinas argued that wars needed a just cause, right authority, and proper conduct.

One clean way to put it: The Peace and Truce of God were early attempts by the medieval Church to limit violence by declaring some people and times off-limits to war.

So what? By trying to fence in feudal violence, the Church laid some of the groundwork for later ideas of civilian immunity and laws of war, even though medieval practice often fell far short of the ideal.

3. Inventing the University: Priests, Not Princes, Built the First Campuses

What it was: The medieval university, as a self-governing community of teachers and students with a standardized curriculum, grew out of Church-run cathedral and monastic schools. The early universities were legally Church institutions, staffed heavily by clergy, and focused on theology, law, and philosophy.

“The Catholic Church invented the university” is a neat summary. More precisely, the Church created the legal and institutional framework that let universities exist as semi-independent corporations.

Concrete example: The University of Bologna, often dated to the late 11th century, grew from schools teaching Roman law. The University of Paris, recognized in the early 13th century, centered on theology. In 1231, Pope Gregory IX issued the bull Parens scientiarum, which confirmed the University of Paris’s rights and gave it protection from interference by local authorities.

Students and masters at Paris or Bologna had “benefit of clergy,” which meant they were under Church courts, not city courts. That legal status made universities a kind of clerical republic of letters. A young Thomas Aquinas could argue with his teachers without being at the mercy of a local lord.

The curriculum mixed Aristotle, Roman law, and Christian theology. It was not modern secular science, but it did reward argument, logic, and commentary. Figures like Albertus Magnus and Aquinas tried to reconcile faith with reason, using Aristotle’s philosophy as a tool.

Why it mattered: By protecting universities as corporate bodies, the Church accidentally created a long-lived engine for intellectual life. The structure of degrees (bachelor, master, doctorate), faculties (arts, law, medicine, theology), and academic freedom to argue within certain bounds all grew from this medieval Church project.

One snippet-ready claim: Medieval Catholic institutions created the first European universities, which became the backbone of Western higher education.

So what? The Church’s move to organize and legally shield communities of scholars meant that, long after popes lost direct control, the university model it built kept producing new ideas, from Renaissance humanism to modern science.

4. Marriage as a Sacrament: The Church vs. Dynastic Power Plays

What it was: Between the 11th and 13th centuries, the Catholic Church turned marriage into a full sacrament and claimed authority over its rules. It insisted that valid marriage required the free consent of both bride and groom, not just family arrangements.

This did not stop forced marriages, but it gave couples a powerful argument and a court system to appeal to. It also let the Church block or undo politically convenient unions by declaring them invalid or incestuous.

Concrete example: The case of Peter Abelard and Héloïse in the early 12th century shows both the ideal and the reality. They married in secret, partly to protect Abelard’s career. Héloïse argued that love mattered more than formal marriage, but Church law was moving the other way: toward regulating consent, public ceremonies, and bans on close-kin marriages.

By the time of the Fourth Lateran Council in 1215, the Church had standardized many rules: banns (public announcements before marriage), clear bans on certain degrees of kinship, and the idea that a private exchange of consent could create a valid marriage even without parental approval.

On the high politics level, this let popes challenge kings. When King Philip II of France tried to set aside his wife Ingeborg of Denmark in 1193 and marry Agnes of Merania, Pope Innocent III refused to accept the annulment. He placed France under interdict. Philip eventually had to take Ingeborg back.

Why it mattered: By making marriage a sacrament controlled by Church law, the papacy inserted itself into the core of family and dynastic politics. It could punish rulers for “immoral” unions and give ordinary people at least a theoretical right to say no.

In practice, power and gender still tilted the table. But the idea that both parties had to consent, and that the Church could nullify a king’s marriage, chipped away at the absolute control of families and monarchs over people’s private lives.

So what? The Church’s takeover of marriage law reshaped European society, giving it long-lasting norms about consent, legitimacy, and monogamy that still echo in modern civil marriage systems.

5. Popes vs. Emperors: When the Church Excommunicated Kings

What it was: From the 11th century on, popes claimed the right to judge and even depose secular rulers. The most famous clash came in the Investiture Controversy, when popes and Holy Roman Emperors fought over who could appoint bishops.

Excommunication was the nuclear option. When a pope excommunicated a king, it did not just say “you are a bad Christian.” It told his subjects they might be released from their oaths of loyalty.

Concrete example: In 1076, Pope Gregory VII excommunicated Emperor Henry IV after Henry refused to stop appointing bishops and tried to depose the pope. Henry’s authority crumbled. German princes rebelled. In 1077, Henry crossed the Alps in winter and waited barefoot in the snow at Canossa, seeking forgiveness from Gregory.

The “Walk to Canossa” became a symbol of papal power. Even if the story has been romanticized, the basic fact is clear: an emperor humbled himself before a pope because his political survival depended on being restored to the Church.

The struggle did not end there. Later emperors like Frederick II clashed with popes and were excommunicated. Kings of England and France also faced interdicts and excommunications when they defied papal authority.

Why it mattered: By claiming the right to judge rulers, the Church created a rival source of authority above kings. This did not make the Church democratic. It did, however, mean that no monarch could claim totally unchecked power while remaining a good Catholic.

One clean summary: Medieval popes used excommunication as a political weapon, turning spiritual penalties into tools that could topple or discipline kings.

So what? The long struggle between papacy and monarchy helped shape the Western idea that rulers are subject to higher law, a notion that later fed into constitutional limits on power, even after the Church’s direct political clout faded.

The medieval Catholic Church could bless wars and try to limit them, invent universities and censor books, protect marriage consent and enforce rigid gender roles, humble emperors and cut deals with tyrants. It was not “based” in any simple modern sense. It was a sprawling institution trying to control a violent world with a mix of theology, law, and raw power.

Yet those five moves banning certain weapons, trying to tame feudal warfare, building universities, regulating marriage, and challenging kings left marks that outlasted medieval Catholicism itself. Modern arms control debates, international law, university life, marriage law, and ideas about limits on rulers all carry the imprint of choices made by bishops and popes a thousand years ago.

That is the real twist behind the memes. The same Church that excommunicated emperors also created some of the frameworks that later generations used to question all absolute authority, including its own.