[citation needed] De Casabianca obtained good grades at the lycée Napoléon, studied law at the University of Paris, and in 1820 he became a member of the bar of Bastia, in Corsica, practicing as a lawyer until 1848.

[1] After the February Revolution, on 23 April 1848 de Casabianca was elected to the constituent assembly as representative of Corsica.

After the presidential election of 10 December 1848 he became one of the most zealous supporters of the president, Prince Louis Napoleon.

When told by Louis-Napoleon of the planned coup the day before it took place, de Casabianca refused on principle to participate and was temporarily relieved of office.

[1] By a decree of 5 March 1864 de Casabianca was named attorney general at the court of accounts.