[1] Cattani Amadori was born in Marradi, and studied at the seminary in Modigliana before being ordained to the priesthood on 5 October 1879.

He then taught at the Modigliana seminary and did pastoral work in that diocese until 1888, when he was named its vicar general.

Raised to the rank of domestic prelate of his holiness on 14 June 1904, he was made apostolic visitor to Marsica in 1909, and papal auditor on 9 February of that same year.

Cattani became secretary of the cardinalatial commission deciding competence questions between Roman congregations in 1921.

Cattani Amadori was one of the cardinal electors who participated in the 1939 papal conclave, which selected Pope Pius XII.