Workshop
19–20 November 2026
ZODIAC - Ancient Astral Science in Transformation (ERC Advanced Grant No. 885478)
Freie Universität Berlin
organizers: Mathieu Ossendrijver, Alessia Pilloni

The invention of the zodiac in Babylonia in the fifth century BCE was a transformative event that affected scholarly and social practices across the ancient world. The zodiac became a central concept for predicting, computing, interpreting, and representing celestial phenomena. The emergence of horoscopy and other astrological practices that cater to private individuals bear witness to a personal turn in astrology. The development of algorithms for computing the zodiacal positions of the planets led to a predictive turn in astronomy. These originally Babylonian innovations were transformed through interactions between culturally, linguistically, and religiously diverse regions and communities. However, there is no satisfactory account of how and why they were able to take root in such diverse contexts.

            This final workshop of the ZODIAC project contributes to a new account of the emergence, development, and first wave of the cross-cultural circulation of zodiacal astral science (ca. 400 BCE – 300 CE). It aims to achieve this by bringing together specialists from diverse disciplines (history of science, ancient philology, ancient history, history of religion, art history) in order to 1) compare the local contexts in which zodiacal astral science was successively adapted across the ancient world; 2) compare the cross-cultural transfer of zodiacal astral science with that of other areas of knowledge and social practice such as mathematics, medicine, and cult; 3) engage with models of innovation, cross-cultural transfer, and theory change.

            Research conducted by ZODIAC and others provides some guidance to this endeavour. The first wave of cross-cultural circulation proceeded within and between multi-cultural empires (Achaemenid, Macedonian, Seleucid, Ptolemaic, Roman) under favorable conditions for innovation and knowledge transfer. Compared to cults, zodiacal astral science benefited from its greater translatability, inclusivity, universality, and scientific status. But its local adaptations vary strongly in time, space, and between different communities. While the uniform zodiac reached the Greek world in the 4th century BCE, the complete package including horoscopy and mathematical astronomy did not reach Egypt and the Greco-Roman world before 150 BCE. The partly foreign (Babylonian, Chaldean, Egyptian) origin of this knowledge is usually not evident in the sources. It is therefore necessary to go beyond classical, static models of innovation, knowledge diffusion, and cultural hybridity and develop a new approach that stresses the diversity of local agency in creating, appropriating, and embedding new knowledge and social practices while acknowledging cross-regional connectivities. Some guiding questions:

            1) Is the cross-cultural circulation of zodiacal astral science between Babylonia, Egypt, the Greco-Roman world, and beyond (ca. 400 BCE – 300 CE) matched by a comparable phenomenon in other areas of knowledge, e.g. mathematics, medicine, and technology?

            2) Can our understanding of this knowledge transfer benefit from new approaches developed for the study of cults in the Roman empire with a perceived foreign origin (e.g. Isis, Serapis, Mithras)? To what extent is astral science (e.g. astrology) a comparable phenomenon?

            3) Did ancient multi-cultural empires (Achaemenid, Macedonian, Seleucid, Ptolemaic, Roman) merely create favorable conditions for cross-regional knowledge transfer or did they also produce specific social or political needs for which zodiacal astral science (e.g. astrology) provided solutions?

            4) How can the conceptual apparatus of globalization, networks, and connectivity contribute to understanding the cross-cultural circulation of zodiacal astral science?

            5) Which other concepts and models used by historians of science, culture, and religion can be adapted to account for the cross-cultural transfer of zodiacal astral science in the ancient world?

More information on the program, venue and registration will follow soon.