I find the age very unrealistic like he tries to focus on actual dates and war for references but Carlo (the real one) was born in 1851 and Duchess Adelaide of Austria died in 1855. So in the novel Carlo is under age and born somewhere before 10 years before the death of Adelaide . Now the current period is 1886 so if we take his real birth then he is 35 and if you take the year in the novel then he is around 41-42 so I would like to ask WTF is the f****** age to be under age in Italy