Secretum secretorum - De Mirabilibus Mundi - Terrestrial
Background for Ars Magica sagas

European Worldmaps of the 12th and 13th Century

by Berenger

Mappa dicitur forma. inde est mappa mundi id est forma mundi

'Map' means shape, hence a map of the world is the shape of the world. (Inscription on the Worldmap of Ebstorf, 13th century)

In 12th and 13th century Europe seeing the shape of the world on a map was a privilege. And what one would see, or expect to see, on it did depend very much on the time, place and social status of one's life. The rather precise knowledge of the Hellenistic world about distances and locations in Southern and Central Europe, the Middle East and North Africa was not completely lost, but as it could not be communicated in writing easily, it was nearly inaccessible even to most monarchs and scholars.

The world map of Agathodaimon

A 12th century copy of Ptolemy's Geographia which was kept in the Vatopedi Monastery on Mount Athos in Greece contains the most precise medieval world map I know. Like a few other copies of the Geographia it contains a map of the known world, referred to one Agathodaimon, of whom nothing is known but the name on the maps. He was probably not a contemporary of Ptolemy, but may have lived in the 5th century AD. The map, over two pages of the book, shows on the left page Europe, including Germany and the Baltic, Northern Africa down to Somalia and the Middle East in rather correct proportions. Ireland, Britain, the western parts of Africa and the rest of Asia, including India and Ceylon, on the right page, are drawn in a tentative way.

The map is designed according to the instructions given in the Geographia itself. It is a cone projection of the globus and gives the degrees of latitude and longitude. It puts the known world between the 63th northern and the 16th southern degree of latitude and has it occupy a full 180 degrees of longitude - without showing an eastern coast of Asia.

Al-Idrisi's maps and the Book of Roger II

Maps like the one of Agathodaimon were not known in medieval Europe, outside of the Byzantine Empire, before the middle of the 12th century. It required the project of a king, in the spirit of the contemporary Toledo school of translators sponsored by the Castilian kings, to retrieve this knowledge. And, of course, the knowledge was provided by Arabian scholars.

Roger II of Hauteville, king of Sicily, had not only dynastic ambitions spanning all the Mediterranean, reaching out for the thrones of Antiochia and Jerusalem, but also a vivid interest in geography. "When king Roger ... found, that these (scilicet: geographical) texts did not treat a subject correctly, he ordered specialists to his court; but after he had disputed with them, he found that their knowledge was not better than that in the quoted books. As he noticed this, he ordered to bring from all his provinces those people who had experience from travels and secure knowledge of these areas. And after he had questioned them on these countries individually or in groups with the help of an interpreter, he gave written form only to those parts of their accounts in which all agreed ... and rejected any controversial point." (All quotes in this chapter from the Book of Roger II).

Around 1140 Roger "ordered to make a disk of pure silver, weighing about 300 pounds, and to partition it in sections". On the surface of this disk (or, according to a modern reconstruction, rectangle of 1.5mx3.5m) a map of the known world was to be engraved, and countries and places added to it when they had been examined. The compilated information about language, customs, religion etc. forms the Book of Roger II, together with many maps. The book stresses, that all engravings in the silver disk were checked for correctness of distances and positions against the accounts of the witnesses.

Scientific head of the project and in charge of the compilation was of course not Roger himself. This was the task of Abu Abdallah Mohammed Ibn Mohammed Ibn Idris, to us known as 'Al-Idrisi', descendant of the Idrisite dynasty of Morocco. He was born in Ceuta, learned in the Cordoba of the Almoravids, travelled through the Maghreb and the Iberian peninsula, to the French and British coasts at the Atlantic ocean and, maybe, to the Asia Minor dominated by the Seljuks. Over about 15 years he gathered information, of course not only from travellers. (The ostentation of empirical methods in the book is significant rather because it anticipates a considerable mistrust of the reader.) Only two of all the authors Al-Idrisi references were not Muslims. This just shows the distribution of geographical knowledge at that time, not any prejudices of Al-Idrisi or Roger. The western half of the copies of Al-Idrisi's map which we know is very similar to the map of Agathodaimon, though it freely adds islands in the Atlantic ocean and makes an attempt to represent Scandinavia - as an island, too. The eastern coast of Asia and the islands of southeast Asia are given in addition - being newly acquired Arabic knowledge. No latitude or longitude is given, and the projection is unclear.

Late Roman itineraria, the Tabula Peutingeriana

The Tabula Peutingeriana is a small part of a copy, made in the 12th or 13th century, of a worldwide Roman Itinerarium, perhaps of the 4th century AD, proving that such maps were still known in our period, though infrequently. These Itineraria are maps concerned only with roads over land, the sequence of the towns along them and their relative, very exactly given, distance. To keep them small and portable during those voyages when they were used, the sea, mountain ranges and all other things between roads are reduced to lines, peninsulas folded up against the continent or incorporated into it, and distances between towns not connected by referenced roads are arbitrarily distorted.

It is significant that such a map of the world was still copied 800 years after it was made, with annotations and updates of diverse ages. Sure, some of the Roman roads given were still in use and many of the towns given still important. But first of all this proves that there were no available contemporary maps coming even close to it.

The Tau maps, Christian symbols and encyclopedias

The Tau maps are, compared to the solitaires presented above, rather frequent in the 12th and 13th century and come in many variants. They are a cross between a map and a symbol of the world. The simplest version you can design yourself in three seconds: draw a circle, then a horizontal straight line cutting it in half and then cut the lower half circle in half again by a vertical line; write 'Asia' into the upper half, 'Europa' into the lower left quarter and 'Africa' into the lower right one - there you are, that's the world. If all went well, the two lines separating the continents look like a 'T', Greek 'Tau', hence the name of this kind of map. Turn it upside down, put a cross on it, and you get the orb in the hand of an emperor.

This symbol represents the world in the hands of emperor Augustus and within the spheres of the planets in the Liber Floridus of Lambertus de St. Omer from 1120, and within the hands of a Christus Pantokrator from the famous scriptorium on the Reichenau. But already in the Liber Floridus this symbol becomes a real map, too, with cities, rivers, seas and mountain ranges.

Imagine the 'Tau' as the Mediterranean Sea, more precisely: its base as the columns of Hercules, its left arm as the Aegean Sea and its right arm as the - Nile and its Delta. Then you get Jerusalem where? - Right, smack in the center of the world. (Well, if you got Atlantis = Santorin there, you were just TOO accurate and should adjust the horizontal bar of the Tau a little downward, as do the designers of these maps.)

The Ebstorf Worldmap

After such beginnings monumental Tau maps were designed. The famous Ebstorf worldmap, unfortunately destroyed by a bomb raid on Hanover in 1943, measured 3.5mx3.5m, more than Roger's silver disk in the reconstruction known to me. Copies of the worldmap from the last century luckily survived the war.

One recent theory gives the concept of this map to Gervasius of Tilbury and dates it between 1241 and 1245, though both is still disputed. (Others dates it around 1280. I am no expert, but for now I assume the more romantic theory above.) Gervasius of Tilbury, an English nobleman born around 1160, studies in Bologna, is 1177 in Venice to observe the negotiations between Barbarossa and Pope Alexander III, goes back to England, and writes a 'liber facetiarum' (yep, a jokebook) for the prince Henry, son of Henry II - the king who had Thomas Becket assassinated. With the prince he flees to France, then to Sicily to the court of William II, grandson of Roger II. When William dies 1189 and the Hohenstaufen inherit Sicily, Gervasius moves quickly on to Burgundy, becomes political advisor of Otto IV, the son of Henry the Lion, great adversary of Barbarossa, and soon is Marechal of the Arelat. After the defeat in the battle of Bouvines 1214, with Otto's hopes for the throne destroyed, he might have moved on to lower Saxony, as did Otto. For him he writes the Otia Imperialia, a book about the wonders and the history of the world, from the beginning until the present time. Otto dies 1218, and from 1223 to 1234 we know of a Propst (praepositus, a reeve cum priest) Gervasius of the nunnery of Ebstorf. The next Propst is known from 1245 on.

From this you can see that Gervasius of Tilbury is as much a man of the world as Al-Idrisi, a scholar, but not a scientist - and certainly a good politician (on the losing side), impresario and entertainer. And closer to the interests and believes of nobles and nuns than Al-Idrisi. The map is a scholar's and polyhistor's work, for sure.

Within the map, you see Christ holding the entire world, his head in far Asia (ex oriente lux), besides the Garden Eden in India - complete with Adam, Eve and the serpent. His right hand is north of Albania, where, as Gervasius knew, do live the amazons under their queens Marpesia and Lampeta, the inhabitants of the city of Terbant and the wild Hyrcanians, which must be guarded least they break out and spread all over the world. All are depicted and described there.

Christ's left hand is in southern Africa, where monstrous humans live: you see the Garamantes, the Psilli, the Siges with the heads of dogs, those people who use their enormous lips to seek shelter from the rays of the terrible southern sun, Ethiopians of twelve feet height and, in the lands of the spear snake Iaculus, those people who can outrun the deer and catch it with their hands. Christ's feet stand outside the columns of Hercules, in the ocean surrounding the known world.

All the tombs of the apostles are found on the map, who spread out all over the world the word of the Saviour and died for it. Jerusalem is at the very center, with its walls and, within, the resurrected Christ. Rome is depicted with the Tiber, the Pantheon, Castel Sant'Angelo, San Pietro and all the other important churches. And, on the very edge of the map, there is Ebstorf itself, with the tombs of its three martyr priests, killed by the pagan Obotrites.


Did I get you into it unawares? I intended to. Were you prepared to accept for a moment that the things I described on the Ebstorf worldmap are more important than the correct distances between places and the right shape of coastlines? Then welcome to the world of medieval nobles and nuns.


Nothing of this text is my own wisdom. I gathered it from:

Birgit Hahn-Woernle: Die Ebstorfer Weltkarte Kloster Ebstorf, 1987 and 1993, ISBN 3-926655-00-3 (No translation available - but has many photographs and one 30cmx30cm representation of the Ebstorf worldmap)

Bernd Rill: Sizilien im Mittelalter Belser Verlag, 1995, ISBN 3-7630-2318-6 (No translation that I knew of)

Plus several good dictionaries and encyclopedias.

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Last modified: Sun Dec 27, 1998 / Jeremiah Genest

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