In early 1865, at the age of 13, Edgardo became a novice in the Canons Regular of the Lateran, adding the Pope's name to his own to become Pio Edgardo Mortara. He wrote repeatedly to his family, he recalled, "dealing with religion and doing what I could to convince them of the truth of the Catholic faith", but received no reply until May 1867. His parents, who were now living in Florence, wrote that they still loved him dearly, but saw nothing of their son in the letters they had received. In July 1870, just before Edgardo turned 19, the French garrison in Rome was withdrawn for good after the Franco-Prussian War broke out. Italian troops captured the city on 20 September 1870.