This volume investigates how Stephen Báthory’s rule in Transylvania and the Polish-Lithuanian Commonwealth reshaped governance, military structures, and the multi-confessional landscape of Central Europe. Bringing together studies on princely administration, justice, finance, culture, mining, diplomacy, and military obligations, the book highlights the mechanisms through which Báthory’s regimes operated across diverse social and political environments. Contributors analyse confessional politics—from Saxon and Szekler communities to Jesuit missions, Unitarian struggles, Jewish and Karaite perspectives—and explore foreign policy toward the Habsburgs, Ottomans, and Western Europe. Intellectual culture, court historiography, memory, visual representation, and the construction of political ideology further illuminate Báthory’s evolving authority as prince and king. Offering the most comprehensive interdisciplinary and international reassessment of Báthory’s reign to date, the volume provides scholars of early modern Central and Eastern Europe with new insights into statecraft, religious plurality, and regional interconnectedness.