Images of Medieval Astrology: The Liber astrologiae

An excerpt from Kristen Lippincott’s introduction to Liber astrologiae (Abū Maʿshar Treatise), a 14th-century manuscript and its beautiful medieval imagery.

The incipits of the prologue and of the first chapter of the manuscript in the British Library, Sloane MS 3983, tell us that it is a copy of the Liber Albumazarus (Liber astrologiae), which has been translated into Latin from the Persian by an otherwise unknown author named Georgius Zothorus Zaparus Fendulus. He describes himself as a sacerdotus (a ‘priest’ or ‘cleric’), philosopher and courtier:


‘Incipit prologus viri cognomine georgius zothori zapari fenduli. G. sacerdotis atque philosophi, translatus de persica lingua in latinum. Liber albumazarus.’ (f. 1ra )

‘… incipit liber astrologie ut cognomine georgij zapari zothori fenduli. G. sacerdotis, philosophi atque prolatum translatus de lingua persica in latinum.’ (f. 1rb)


Taking this list of professions into consideration alongside a stylistic analysis of the earliest surviving manuscript of the text (Paris, Bibliothèque nationale de France, Latin 7330), scholars have proposed that Fendulus was probably a cleric associated with the Sicilian court sometime during the second half of the twelfth century.

The author’s prologue begins with a fabricated account of how he came upon the current text during his travels through Babylon and Persia, having already translated numerous texts from Persian and Syriac into Latin. He claims to have translated it from the Persian and Indian languages into Latin and adds that he took great pains to provide a corrected copy of the text. In fact, the bulk of the text has simply been copied from Hermann of Carinthia’s Latin translation of Abū Maʿshar’s Great Introduction to Astrology.

The text itself opens with a very brief summary of the basic astronomical and astrological knowledge that one might need in order to understand the structure of the cosmos, including a discussion of the planets and their orbs, of the 1022 stars and of the 48 constellations into which the Ancients arranged the stars into recognisable figures from their own mythologies. He also presents a series of astrological concepts, such as the different qualities that the twelve signs of the zodiac possess and bring to bear on events on Earth.

Cancer, ff. 13v-14r

The next section (ff. 3r–30v) is divided into twelve chapters, each of which focuses on one of the twelve signs of the zodiac, beginning with Aries, the Ram, and ending with Pisces, the Fish. Each chapter opens with a text that summarises the astrological qualities of that sign and then lists the constellations or parts of a constellation that are said to rise above the horizon alongside each zodiac sign. These groups of stars were called paranatellonta (παρανατέλλοντα, ‘rise beside’) or sunanatellonta (συνανατέλλοντα, ‘rise with’) by the Greeks, who compiled catalogues of the stars that rose above the horizon for each degree of the ecliptic.


Rather than present a long list of paranatellonta for the entire 30° of each sign, Abū Maʿshar follows the tradition of dividing each sign into three equal sections of 10° each. These segments of 10° are usually referred to as ‘decans’ (from the Greek δεκανός, dekanos).

In terms of understanding the basic structure of the Sloane manuscript, however, it is useful to know that when Abū Maʿshar was compiling his list, there were several competing traditions in which the astronomical knowledge and astrological lore associated with the paranatellonta were circulating. Since the details of these different traditions varied significantly, Abū Maʿshar decided to present three different versions of this material in parallel and, thus, he describes a series of images associated with the rising of every segment of 10° (or decan) for each zodiacal sign:

  • First, ‘according to the Persians, Chaldeans and Egyptians’. Previous scholars have traced the primary authority behind these images to the writings attributed to Teucer, the Babylonian, which was available to Abū Maʿshar through a Pehlevi (Persian) translation that had been made in AD 542.
  • Second, ‘according to what the people of India have agreed upon,’ which are a series of Indian asterisms, first recorded in the sixth-century writings of Varāha Mihira.
  • Third, ‘the 48 constellations that the two sages, Aratus and Ptolemy, have mentioned’.

In the Latin translation of this passage by Hermann of Carinthia, he has kept all these subtle distinctions, but in the version compiled by Fendulus, he has reduced the credit for these systems into simply: ‘the Persians’, ‘the Indians’ and ‘the Greeks’.


Following the text for each sign, there is a full-page depiction of the zodiac sign itself with three full-page illustrations of the paranatellonta for each decan of that sign:

  • the top register illustrates the figures ‘according to the Persians’;
  • the middle register contains depictions of the decan-gods ‘according to the Indians’;
  • the bottom register contains depictions of the parts of the constellations ‘according to the Greeks’.

There are two main reasons why it is so challenging to decipher the images of the paranatellonta that are presented in the Sloane manuscript. The first is that there seems to be no real understanding of the iconography of the Greco-Roman constellations by the illuminator of the manuscript. This is most noticeable in the high degree of gender fluidity between the Greco-Roman mythological figures and their renderings, but it is also evident in a lack of differentiation amongst the many depictions of ‘fish’ (Delphinus, Pisces, Cetus and Piscis Austrinus); ‘snakes’ (Draco, Serpens and Hydra); ‘horses’ (Pegasus, Equuleus, Centaurus and the horses that sometimes appear in the illustrations of Auriga and Boötes); and the ships, boats and stylised segments of water that are distant reflections of Argo and Eridanus.

This confusion is not due solely to a single inexpert illuminator, however, but it reflects a more pervasive challenge that arose from the complex series of changes that constellation imagery sustained during its long migration from its Greco-Roman origins through a series of Persian, Indian and Arabic intermediaries before returning to the Latin West.

Draco, ff. 24v-25v

Most of the unusual names for the Greco-Roman constellations that appear in the text and the labels in all three registers can be traced back ultimately to the Latin translations or transliterations of the misunderstandings by the Arabic authors of Greek names or the significance of the mythology from which their names were derived. These include:

  • Lyra being called vultur cadens (‘the falling vulture’) or testudo or tortuga (‘the turtle’ or ‘tortoise’) – the latter referring to the mythological invention of the lyre by Hermes/Mercury from the shell of a tortoise. It is also sometimes called musculus¸ which must have originally indicated the ‘little shell’ of the tortoise, but then came to be understood as ‘the little mouse’.
  • Cygnus described as gallina (‘the hen’).
  • Cassiopeia as sedes (‘the seat’), thronus (‘the throne’) or habens palmam delibutam (‘having stained hands’).
  • The head of Medusa becomes the decapitated head of a bearded man (caput algol).
Vultur cadens, f. 11r

The second reason why it is so challenging to decipher the images of the paranatellonta is due to the numerous mistakes that have been introduced by Fendulus as well as by the subsequent scribes and of his text. These errors, in turn, have generated their own consequences when it comes to the illustrations. One example should suffice. There is a figure in the first decan of Scorpio (f. 23v) that is described as ‘Caput gorgonis quod alane dicitur’ (‘the head of the Gorgon which is called alane’). The name of alane, however, reflects the faulty transcription by the scribe and it should read alaue., which stems from the Arabic term al-ʿawwā (the ‘Howler’). It was the name given to the Greco-Roman constellation of Boötes on the mistaken assumption that the name of this constellation in Greek (Βοώτης) is derived from βοητής (‘the Shouter’). In this case, then, the constellation cited here ‘according to the Greeks’ should represent Boötes; but the figure depicted in the paranatellon has somehow become entangled with the image of the head of the Medusa, which is held by the constellation of Perseus.

Perseus holding the head of Medusa (the Gorgon), f. 23v

The second set of images (ff. 32r–49r) depict the seven planet-gods (Saturn, Jupiter, Mars, Sol-Apollo, Venus, Mercury and Luna), each of which is dressed in fourteenth-century costume. Each planet-god is depicted four times, illustrating how the combination of each planet with a particular zodiac sign affects that planet’s power. The sequence runs as follows:

  • Domus (House), the zodiac sign or signs in which the planet-god is ‘at home’ and his or her power is most stable.
  • Declinatio (Detriment), the signs where the power of the planet-god is ‘blighted’ or ‘inflected’ by the limiting power of the planet-god whose natural home is there.
  • Exaltatio (Exaltation), the signs in which the planet-god’s power is ‘enhanced’ or ‘exalted’ due to the sympathy he or she has with the lord of these signs.
  • Casus (Fall), the signs in which the planet-god’s power is blocked through the antipathy of that sign’s own planet-god.
Mars (house, detriment, exaltation and fall), ff. 37r-38v

Finally, in addition to the illustrated text of the Liber Albumazarus, there is a horoscopic diagram recording the orientation of the sky at the birth of Christ on folio 49v, with an accompanying text, which has been written in a later hand. The horoscope of Christ was a contentious topic throughout the Middle Ages and Renaissance and, at certain times, the act of calculating the exact time of Christ’s birth was considered to be heretical. The first recorded attempts were made by the Arabic astrologer, Māshāʿallāh (AD c.740–c.815), but the most widely disseminated description of the astrological conditions of Christ’s birth appears in Book VI of Abū Maʿshar’s Great Introduction to Astrology. The version in the Sloane manuscript has been taken from the Speculum astronomiae of Albertus Magnus, which follows the Latin translation of Abū Maʿshar by Johannes Hispalensis.

Leo and its first decan, ff. 16v-17r

The seven surviving Fendulus manuscripts tell an interesting story about the fate of an unusual work. At face value, the text of the Liber Albumazarus is neither innovative nor tremendously practical, but it does provide a convenient résumé of what a serious astrologer would probably more happily find in one of the more reliable versions of either Latin translation of Abū Maʿshar’s Great Introduction to Astrology (Johannes Hispalensis’ and Hermann of Carinthia’s). The addition of illustrations, however, transforms this somewhat questionable offering into a sumptuous luxury object or, as the essay on these manuscripts in the Sternbilder des Mittelalters volumes phrases it, the production is ‘primarily a picture book … [with] an obvious courtly claim’. Indeed, interest in the Liber Albumazarus seems curiously limited – the book’s production arising from within the wealthy, multi-cultural ambience of the Imperial court in Sicily and then finding its natural second home in the extended lands of the Burgundian aristocracy. Once the demand for this particular kind of luxury object waned, the desire to create another copy of the text seems to have disappeared.

This was an excerpt from the commentary volume of the Liber astrologiae (Abū Maʿshar Treatise) by Kristen Lippincott (The Saxl Project). The facsimile editions of the Liber astrologiae and other illuminated manuscripts are available at

Liber astrologiae (Abū Maʿshar Treatise) – British Library, Sloane MS 3983