He dedicated much of his time in later years to writing. According to some of his critics, as a historian Mitre took several questionable actions, often ignoring key documents and events on purpose in his writings. This caused his student Adolfo Saldías to distance himself from him, and for future revisionist historians such as José María Rosa to question the validity of his work altogether. He also wrote poetry and fiction (Soledad: novela original), and translated Dante's "La divina commedia" ("The Divine Comedy") into Spanish. He was also an active freemason, and the grandfather of poet, Margarita Abella Caprile.