Shakespeare’s Second Tetralogy explores the profound and multifaceted relationship between William Shakespeare’s historical dramas and biblical intertextuality. This study moves beyond reductive compilations of biblical references or sectarian interpretations, delving instead into the aesthetic and stylistic functions of these intertextual elements in Shakespeare’s second tetralogy. The book’s originality lies in the way it examines how biblical allusions and echoes shape characters, situations, and narrative structures, offering a nuanced understanding of Shakespeare’s creative integration of scripture. By treating these intertexts not merely as theological or moral markers but as rhetorical and artistic tools, the study reveals new dimensions to Shakespeare’s engagement with the Bible. The research situates Shakespeare’s historical dramas within the important context of Anglo-Iberian intellectual exchanges. It re-examines Shakespeare’s Spanish sources, particularly in relation to the theories of kingship and natural law proposed by the School of Salamanca, and draws on the works of the Dominican Francisco de Vitoria to explore themes of sovereignty and modernity. This approach highlights how Shakespeare updated mediaeval characters and ideas while retaining their traditional elements, creating complex portrayals that resonated with both Renaissance and contemporary audiences. By intertwining literary analysis with historical research, the study underscores the structural and thematic importance of biblical imagery in shaping Shakespeare’s vision of kingship. The book therefore addresses a critical gap in Shakespeare studies, offering scholars and students a fresh perspective on how biblical intertexts function as dynamic aesthetic and political tools in his plays.