He was a member of the papal conclave that elected Pope Pius V and was named vice-protector of Germany.
Zaccaria Delfino was born in Venice on 29 March 1527, the son of a Venetian patrician family.
[1] In January 1555, he accompanied Cardinal Giovanni Morone, papal legate a latere, to the Diet of Augsburg.
[1] He received the red hat and the titular church of Santa Maria in Aquiro (a deaconry raised pro illa vice to the status of title) on 7 September 1565.
[1] On 15 April 1578, he opted for the titular church of Santo Stefano Rotondo, and later for Sant'Anastasia al Palatino on 17 August 1579.