Antonio de Erauso, born as Catalina de Erauso (in Spanish) (San Sebastián, Spain, 1585 or 1592 — Cuetlaxtla near Orizaba, New Spain, 1650), was a Basque nun and explorer. He also went by Alonso Díaz and some other masculine names, later taking on the name Antonio de Erauso which he went by for the remainder of his life. He is also known in Spanish as La Monja Alférez (The Ensign Nun or The Nun Lieutenant). de Erauso was originally an unwilling nun, but escaped the convent and travelled around Spain and Spanish America, mostly under male identities, in the first half of the 17th century. Erauso’s story has remained alive through historical studies, biographical stories, novels, movies and comics.