[2] On 20 July 1626, he was appointed new Archbishop of Messina upon request of Philip IV of Spain, who had the advowson to present to the Pope the nominee for such office.
The episcopal consecration followed on 8 November in San Giovanni dei Fiorentini by the hands of Cardinal Giulio Cesare Sacchetti.
[4] Biagio Proto was accused by people and by the Senate of Messina of using his jurisdictional powers for extortions, and of avarice and simony.
The result of the investigation supported the charges, however Biagio Proto was acquitted in 1639 and returned in Messina to rule his diocese.
[2] He died on 7 April 1646 in Milazzo,[1] and his remains were moved and buried in the Cathedral of Messina, where his tomb still is visible.