Between the 12th and 16th centuries, Europe experienced the golden age of Western astrology: the discipline established itself in universities, advised rulers, and shaped learned medicine. It was also the period when the first rigorous criticisms emerged, foreshadowing the upheavals to come. This dual movement, of peak and questioning, makes this era a decisive turning point in the history of astrology.
From around the 12th century, Latin Europe massively rediscovered Greek and Arabic knowledge through the great translations circulating from the Iberian Peninsula and Sicily. Astrology entered the nascent universities, where it was taught as an auxiliary discipline to medicine: the learned physician was expected to understand celestial influences in order to interpret constitutions and guide treatments. At the same time, princely and papal courts surrounded themselves with dedicated astrologers, whose advice was sought on political, military, and dynastic decisions.
This dual footing, academic and courtly, gave astrology an unprecedented institutional legitimacy in the West. The Renaissance, from the 15th century onward, further amplified this prestige by linking the study of the stars to the grand intellectual ambitions of Florentine Neoplatonism and humanism.
This period saw the consolidation of several lasting technical and theoretical achievements. University teaching standardized astrological medicine: birth charts and planetary ingresses became recognized tools of learned diagnosis. At the same time, the system of dividing the sky into houses was the subject of mathematical formalization work that considerably refined practice, notably through the contributions of Regiomontanus.
On a philosophical level, Florentine Neoplatonism integrated astrology into a vision of the cosmos in which celestial bodies act as intermediaries between the divine principle and earthly matter. This orientation gave the discipline a new speculative depth, far removed from purely technical calculation. As a counterpoint, the late 15th century saw the emergence of serious philosophical and theological criticism, which forced defenders of astrology to clarify their arguments and their limits.
Guido Bonatti, active in the 13th century, is one of the most representative figures of the medieval court astrologer: an advisor to princes and condottieri, he embodies the practical and political role the discipline could play at the time. Regiomontanus, in the 15th century, made a decisive contribution to the mathematical formalization of the house system, whose logic of sky division continues to be used and debated by practitioners today. Marsilio Ficino, a Florentine philosopher of the 15th century, situated astrology within the framework of Neoplatonism: for him, planetary influences were part of a universal sympathy connecting all parts of the cosmos.
At the turn of the 15th and 16th centuries, Giovanni Pico della Mirandola took a radically opposite stance. In his work Disputationes adversus astrologiam divinatricem, he developed a systematic critique of divinatory astrology, challenging both its theoretical foundations and its practical claims. This text represents one of the first major philosophical challenges to the discipline in the West, and its influence would be felt well beyond the Renaissance.
The medieval and Renaissance period bequeathed to Western astrology a technical and symbolic body of work of remarkable coherence: the house system derived from Regiomontanus's work, astrological medicine codified in universities, and the Neoplatonic vision of correspondences between sky and earth are all foundations that later practice would continually revisit, adapt, and debate. What you encounter today in birth charts, with their twelve numbered houses and their meanings tied to the body and concrete life, bears the direct imprint of this European golden age.
Pico della Mirandola's critique, for its part, foreshadows the debates that would intensify in the 17th and 18th centuries, when the scientific revolution called the epistemological status of astrology into question more deeply. The medieval and Renaissance peak is thus both a summit and a tipping point in the long history of the discipline.