“During the Middle Ages, scholars thought the Earth was round.”

“By the 5th century B.C., it was widely accepted that the Earth is a sphere. This is a critical point, as there is a widespread misconception that ancient peoples thought the Earth was flat. This was simply not the case.” The article notes that Greek arguments for a spherical Earth (e.g., lunar eclipses, ships disappearing hull-first) became standard and that this cosmology was transmitted into later periods, forming the background for medieval learned traditions.

Discussing medieval Christian cosmology, the entry notes that medieval scholastic authors worked within “the broadly Aristotelian–Ptolemaic worldview, in which the Earth is a sphere at the center of a series of concentric celestial spheres.” It describes how thinkers such as Thomas Aquinas integrated this geocentric, spherical Earth model into their theological and philosophical systems rather than questioning the Earth’s sphericity itself.

In their influential essay on medieval cosmology, David C. Lindberg and Ronald L. Numbers argue that the notion that medieval Christians believed in a flat Earth is a myth: they write that in the Latin Middle Ages "there was scarcely a Christian scholar who did not acknowledge the sphericity of the Earth" and that the approximate size of the globe was also commonly known among educated people.

In chapter 32, Bede explicitly describes the Earth as spherical: "The reason why the same days are of unequal length is the roundness of the Earth, for not without reason is it called 'the orb of the world' … It is, in fact, a sphere set in the middle of the whole universe. It is not merely circular like a shield, or spread out like a wheel, but resembles more a ball, being equally round in all directions." This seventh‑/eighth‑century Christian scholar directly presents the Earth as a sphere.

In its discussion of medieval cosmology, Britannica notes that educated Europeans in the High Middle Ages operated within an Aristotelian–Ptolemaic system: “The universe was conceived as a series of concentric spheres with the Earth, a globe of earth and water, at the center.” It emphasizes that this geocentric model, not a flat‑earth view, framed scholastic philosophy and theology.

“It seems there’s one fact about the Middle Ages that always seems to astound people: medieval people did not actually think the world was flat… Al-Farghani was not the only one who noticed: the Earth is described as a sphere by the Venerable Bede (seventh century), Roger Bacon (thirteenth century), and Thomas Aquinas (also thirteenth century), among others… The fact that the Earth’s spherical shape was widely accepted is shown by the use of orbs as a symbolic part of royal regalia, and in pictures of Jesus, ‘The Saviour of the World’ (Salvator Mundi).”

The truth is, Columbus's peers generally believed Earth was round. In fact, the awareness of a round Earth dates back at least to Pythagoras during the 6th century BC. The popular story that medieval Europeans thought the Earth was flat is presented here as a debunked historical myth.

Columbus and all his detractors knew that the earth was round. The myth that medieval Christians believed in a flat Earth is described as a 19th-century fabrication, while the real dispute around Columbus was the size of Earth and the feasibility of the voyage.

The medieval flat-Earth story is traced to later writers, not to the beliefs of medieval scholars. The article states that the idea that Columbus had to prove the Earth was round is false and that learned people in the Middle Ages generally knew the Earth was spherical.

“Columbus argued that Earth was smaller than was commonly believed. The shape of the earth wasn’t in question… Yet this story simply isn’t true. In fact, most people at that time believed the earth to be round… ‘With extraordinary few exceptions no educated person in the history of Western Civilization from the third century B.C. onward believed that the earth was flat.’ … Early church father Augustine (354–430), for example, accepted a round earth, and medieval theologian Thomas Aquinas (1225–1274) employed ancient Greek arguments for a spherical earth.”

One commonly held idea about the Middle Ages is that most people believed the Earth was flat … But this is yet another misconception foisted upon the people of the medieval period. As it turns out, folks in the Middle Ages were not nearly as ignorant of basic geographical and astronomical facts as we tend to believe. Not only did most educated people in the Middle Ages know the Earth was round, but this knowledge also had been common among scholars since antiquity. By the 13th century, the Earth’s spherical shape was regarded as established scientific fact, with influential scientists, thinkers, and clergymen such as Thomas Aquinas, Roger Bacon, Albertus Magnus, and Johannes de Sacrobosco all agreeing with this premise.

This article examines when the spherical Earth idea emerged in Greek thought and argues against common overstatements about its antiquity: "All this strongly suggests that no one proposed that the Earth is a sphere until a few decades before Plato noted the idea in the 370s. Thus, the common statement that the Greeks knew the Earth to be round from the 6th or 5th centuries BC is unjustified." While focused on antiquity rather than the Middle Ages, it shows that even among Greek philosophers there was earlier debate and that certainty about Earth’s sphericity developed over time.

From the 13th century onward, John of Sacrobosco’s ‘Tractatus de sphaera’ (‘Treatise on the Sphere’) was a standard introductory astronomy text at European universities. The work explicitly treats the Earth as a sphere and gives arguments for its sphericity (such as the curved shadow on the Moon during eclipses and the changing position of stars with latitude). Its widespread use across medieval universities indicates that the spherical Earth model was part of the basic training of scholars in the later Middle Ages.

The article comments: “It is a common misconception that during the Middle Ages people believed that the Earth was flat. Such cosmological beliefs were perhaps popular among peasants and uneducated folk, but the scholars of the time were well aware of Earth’s spherical shape.” It further notes that “The fact that the Earth is round has been widely accepted by the intellectuals of the Western world since the period of Ancient Greece.”

This creationist article argues that many ordinary people may have held flat‑earth ideas: “Although scholars knew the Earth was round, it is likely that a number of common folk in the Middle Ages pictured the world as flat or as a disk surrounded by ocean, based on their reading of Scripture or local tradition.” However, it concedes, “Medieval academics generally followed the classical view that the Earth was a sphere, as taught by Aristotle and others.”

Some critics of Christianity still allege that during the Middle Ages the church taught that the earth was flat and persecuted those who disagreed. However, this charge is largely based on later anti-Christian propaganda. While a few obscure writers may have questioned the earth’s sphericity, the mainstream of medieval Christian scholarship followed classical authorities in teaching that the world is round.