[1] He served as prelate of the Sacred Congregation of the Council before being appointed vice-legate to Urbino in December 1755.

[1] He was appointed to the Apostolic Camera in June 1764, returning to Rome and taking possession of that office in January 1765.

[1] Pope Pius VI made Altieri a cardinal in pectore in the consistory of 23 June 1777.

[1] Altieri received the red hat on 14 December 1780, and was awarded the deaconry of San Giorgio in Velabro.

[1] He was appointed to the Sacred Congregations of Bishops and Regulars, Council, Acque and Good Government.