Born in 1822 (i.e. one year after the death of Napeleon the Ist) in Trieste as an exile, prince Napoleon-Joseph-Charles-Paul Bonapate grew up in Rome where his parents King Jerome and Queen Catherine were eventually authorized to stay after years of uncertainty.
Being near his grandmother Letizia « Madame Mère » who found he had « an Emperor’s medal for a face » the young prince came to understand that his resemblance with his deceased uncle constitutes an asset to be remarked among his own and considered by the many followers of his family.
Contrarily to their elder brother Jerome, who was sent in 1832 to Stuttgart under the supervision of his uncle King Wilhelm Ist of Wurtemberg, Mathilde and Napoleon stayed with their parents and remained close to one another. In Rome and in Florence from 1831 on, they received a deep but often interrupted education. Mathilde later wrote : « Nothing was ever missing from us. But the greatest justice I must concede to my parents is to have given us perfect principles. They taught me to love France and love freedom. »
The death of their mother in Lausanne (1835) marked the end of blissful carelessness for the both of them but also the start of a relationship between Plon-Plon and the future Napoleon the IIIrd, who became something of a tutor to his young cousin for a few months. Hortense de Beauharnais had indeed asked her brother-in-law Jerome to welcome her youngest son to Arenenberg in his beautiful villa overlooking the Constance Lake. This parenthesis of sorts was an important time for both cousins and remained so for their whole lives. Despite an often conflicted relationship, a deep tenderness united them always.