Became a Jesuit in 1749, then Archdeacon of Cesena Cathedral (as appointed by his brother the pope). He is the author of De Majorum Suorum Ladibus Carmen (where his name is given as Hyacinthii Ignatius, latin for Giacinto Ignazio) which is a poem written to Barnaba his brother (and future Pope Pius VII), whilst the latter was still Bishop of Immola. In this Latin poem, he recounts the history of the Chiaramonti family and other important related people.
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