He was born in Buenos Aires, belonging to the distinguished family of Domingo Belgrano, a rich merchant of Genoese origin and María Josefa González, born in the city. After having completed his elementary studies in the Colegio San Carlos, he moves to Spain entering to serve as a Guardia Corps, and taking part in the actions of El Ferrol against the English in 1800. On his return to Buenos Aires, he wrote "Rasgo histórico poético", a composition on the occasion of the English invasions.