This thesis investigates the martyr drama as a literary genre in 16 th and 17 th century European theatre. It argues that Christian martyr literature provided the core formal elements of plot and character for hundreds of dramatic works across the continent in the period. These adaptions of Christian martyr stories from prose literature resulted in a new dramatic form, which depicted human existence as a spectacle of worldly suffering and otherworldly faith. This thesis shows how the martyr drama appeared in various iterations across different theatre traditions, offering a catalogue of 234 works of the genre between 15-1700 as an appendix. It focuses its in-depth analyses on a smaller number of works of Spanish, French, and German theatre in the period 1600-1650, where notable playwrights such as Lope de Vega, Pedro Calderón de la Barca, Pierre Corneille, Jean Rotrou, and Andreas Gryphius took to the genre. These readings shed light on the significant influence of Christian hagiography on European theatre in the period, showing how playwrights of different confessions and national traditions adopted the characters of the martyr and the persecutor as well as plot scenes of imprisonment, interrogation, and execution. To understand how the martyr dramas were received by contemporary readers and theatre audiences, this thesis investigates the extensive discussions of the legitimacy of theatre and its adoption of religious subjects in the period. While some defended the martyr dramas as playful treatments of religious truth, others rejected them as profanations of holy matters. These discussions surrounding early modern martyr dramas show how European theatre developed as a secular institution in the period in ongoing negotiation with the church, and that standard narratives of secularization fail to describe how representatives of both institutions were decisive in this process.