The Politics of Astrology in Renaissance Hungary

One of the highlights of the Diet of Presburg in 1468 was a debate between two Polish astrologers, Martin Bylica and Jan Stercze. At issue was the proper interpretation of a geniture that Stercze had calculated in 1467 for János Rozgon, a Hungarian Count. Upon reviewing the geniture. Bylica declared that Stercze’s interpretation was founded on erroneous astrological principles. Stercze defended his interpretation in a series of letters to Rozgon, but the matter remained unresolved until the Diet of Presburg the following year. In front of the Hungarian king Matthias Corvinus and the rest of the Diet, Bylica and Stercze publicly debated the proper astrological techniques and the appropriate methods of interpretation. Corvinus judged the dispute and in the end declared Bylica the winner. Bylica was awarded 100 florins and, more importantly, became Corvinus’s principle astrologer and political advisor — a few years later, Bylica boasted that the king consulted with him on all important matters and rarely traveled without Bylica by his side. Stercze, by contrast, appears to have spent the remainder of his life in a small town in Transylvania.

This debate provides a glimpse of the social and politic context for Renaissance astrology. The dispute between Bylica and Stercze spilled out of the erudite circles of academically-trained astrologers and into the powerful world of royal politics. The fact that their contest was an important event at the diet in 1468 locates their astrology at the center of Corvinus’s politics. It also suggests that the practice of astrology included public performance. Unlike academic disputes, which were tightly circumscribed by rules, court disputes were governed by the intellectual and aesthetic interests of the prince. To succeed in the courtly arena required erudition and showmanship. Bylica had mastered both. It is no surprise that he was handsomely rewarded with Corvinus’s generous patronage for the remainder of his life.

A horoscope cast by Martin Bylica for Matthias Corvinus’s Coronation in 1464.

I intend to use Martin Bylica’s career as a window into the courtly and political world of Renaissance Hungary. In his roles as court astrologer, political advisor, university professor, and emissary Bylica maintained wide network of important patrons and colleagues both inside and outside Hungary. Existing scholarship has established the chronology of Bylica’s life and has indicated his relationships to other important Renaissance scholars, such as the Cardinal Pietro Barbo (later Pope Paul II), the brilliant German astronomer Regiomontanus, the Viennese instrument maker Hans Dorn, the humanists Janus Pannonius and Johannes Vitez, and the Hungarian king Matthias Corvinus. The questions that have motivated previous scholars, however, focus on elucidating the context for Nicholas Copernicus’s intellectual development. Consequently, Bylica’s career is examined less for what it reveals about his own context than for how it contributed to Copernicus’s achievement.

My project addresses two lacunae in the historical scholarship: What was the content of Bylica’s work? And what was the context for that work? By concentrating on the content of Bylica’s texts, I intend to reconstruct his understanding of the practice of astrology, including its techniques, canons, and goals. At the same time, this focus on Bylica’s texts will reveal the people and events that stood at the center of his astrological efforts. Constructing a prosopography of these people and events will, in turn, help me recover the people for whom he was practicing that astrology and in what contexts.