The aim of this thesis is to advance an understanding of the author's corpus of tragic plays, eight in total. Chapter One explores continuities and changes in Galvez's critical fortunes in the last two hundred years. Chapter Two examines the author's commitment to write tragedy in the light of notions of the genre in eighteenth-century Spain, situating Galvez's innovation and experimentation with generic constants both ancient and modern in the context of the contemporary debate on theatre. The remaining eight chapters are dedicated to analyses of aesthetic, structural and thematic elements of each play: Afi-Bek, set in Mameluke Egypt, whose ensemble cast of characters and uncompromising portrayal of cruelty and barbarity perplexed contemporary critics; Safil, which dramatised the final hours in the life of this Biblical figure in the uni-personal melologo format; Safo, which depicted the Greek poet's passionate yet solemn act of suicide; Florinda, which interrogated the legend of the Moorish Conquest of Spain; Blanca de Rossi, in which elements of the emergent Gothic style animated the familiar tragic dilemma between public duty and personal honour; Amnon, which recast the Biblical story of Amnon and Tamar and engaged with earlier treatments by Calderon de la Barca and Tirso de Molina; Zinda which addressed issues of slavery, colonialism and nationhood, drawing on elements and techniques associated with sentimental comedy; La delirante, in which Galvez approached the historical account of the rivalry between Tudor and Stuart, through the character of Leonor, Mary Stuart's daughter. The systematic analysis of these plays reveals Galvez as a self-conscious and skilful tragedian, able to fuse the conventions of ancient models of tragedy with the devices of new dramatic and literary forms to create a body of tragic writing which is at once experimental, innovative and essentially classicising.