Biography and works
Born in Rome, he was the godson of Pope Innocent XII, and a member of the notable Alfieri family of Piedmontese origin (the well-known dramatist Vittorio Alfieri was his nephew). In Rome, Benedetto was educated in mathematics and design by the Jesuits; he then moved to Piedmont (living in Turin and Asti) to practice both as a lawyer and as an architect. He was frequently patronized by Charles Emmanuel III of Sardinia, who commissioned him with the design of the Royal Theater of Turin; the theatre (which was probably his masterwork) burned down in 1936.
He also completed the bell tower of the church of Santa Anna in Asti; designed the Palazzo Ghilini in Alessandria; helped complete the facade of Vercelli Cathedral (1757-1763); aided in the decoration of the interior of the Basilica of Corpus Domini in Turin and the decoration of Palazzo Chiablese, adjacent to the Royal Palace in Turin. He also contributed additions and extensive decoration of the Palazzina di caccia of Stupinigi. He designed the bell-tower of the Basilica of San Gaudenzio in Novara. He also completed the neoclassical façade of Saint Pierre Cathedral in Geneva. The King made him Count of Sostegno.
- Boni, Filippo de' (1852). Biografia degli artisti ovvero dizionario della vita e delle opere dei pittori, degli scultori, degli intagliatori, dei tipografi e dei musici di ogni nazione che fiorirono da'tempi più remoti sino á nostri giorni. Seconda Edizione.. Venice; Googlebooks: Presso Andrea Santini e Figlio. p. 15.