This article examines Sebastián Durón’s opera La guerra de los gigantes (c. 1701–3) in the context of the early years of the War of the Spanish Succession (1701–14) and Philip V’s reign (1701–46), as well as the development of opera in Madrid. It presents three main arguments. First, I argue that the character of Minerva in this opera was intended to symbolise Maria Luisa Gabriela of Savoy (1688–1714), the bride and future queen consort of Spain. The aristocrat who commissioned La guerra de los gigantes sought to portray Maria Luisa not only as an ideal wife and woman but also as a powerful military and political ally to King Philip V during the war. Second, I propose that La guerra de los gigantes is part of a broader ‘theatre of loyalty’ that emerged during the early years of Philip V’s reign and the War of the Spanish Succession. This type of theatre allowed Spanish noblemen, particularly the grandees, to express their allegiance to their new king, gain his favour, and enhance or solidify their power. Finally, I suggest that La guerra de los gigantes represents one of several attempts by the Spanish high nobility to develop the genre of opera in Madrid, at a time when partly sung musical dramas such as the zarzuela were the dominant theatrical forms.