Giacomo Cavalieri was born in Rome in 1565 to Giacomo Cavalieri and Diana Santori, related to the Borghese and Paluzzi Albertoni families. He became referendary of the Tribunal of the Apostolic Signature in the Roman Curia and governor of Faenza and Città di Castello and auditor of the Roman Rota. On September 15, 1623 he was appointed datary of His Holiness. Pope Urban VIII created him cardinal priest in the consistory of January 19, 1626. He opted for the title of Sant'Eusebio on February 9, 1626. He died on January 28, 1629 in Tivoli.