Born in the Campo Marzio district of Rome, he owned a small carting business and became involved with the movement for the political unification of Italy.

Writing in the Dizionario Biografico degli Italiani, the historian Maria Luisa Trebiliani gives two possible explanations for the name: 1) the Roman statesman and orator Cicero, to whose eloquence Brunetti was compared, or 2) a puerile term of endearment derived from the Italian ciccio ('chubby') and the Romanesco rocchio ('piece').

After receiving a simple education, Brunetti started working as a cart driver, transporting wine from the Roman Castles to the city.

[2] In the following two decades, he greatly expanded the size of his transport business, and begun delivering hay and cereals to customers including the Ospedale di Santo Spirito in Sassia.

[1] In 1835, encouraged by the Italian nationalist Mattia Montecchi [it], he became a member of Young Italy, a unification movement led by the activist Giuseppe Mazzini.

When the city was captured by the French, Brunetti accompanied Giuseppe Garibaldi, the military leader of the Republican forces, on his northward retreat towards Venice.

[1] On 9 August 1849, Brunetti, his sons, and a small group of Republicans were captured by troops of the Austrian Empire before crossing into Venetian territory.