[2] [3] It is claimed, dubiously, that Bishop Bernardus transferred the seat of the diocese of Vado to Savona in 966, and that the action was confirmed by Pope Gregory V in 995.

[6] In 1239, Cardinal Giacomo da Pecorara, suburbicarian Bishop of Palestrina, was sent by Pope Gregory IX to France as papal legate, to deal with the Albigensian heresy.

[11] In 1544, Pope Paul III ordered that the church of S. Francesco should be elevated to cathedral status and the adjacent Franciscan convent converted into an episcopal palace.

[12] The new building was completed in 1602 and dedicated by Bishop Pietro Francesco Costa on 24 April 1605 in honor of the Assumption of the body of the Virgin Mary into Heaven (S. Maria Assunta).

[15] Following the Second Vatican Council, and in accordance with the norms laid out in the council's decree, Christus Dominus chapter 40,[16] Pope Paul VI ordered consultations among the members of the Congregation of Bishops in the Vatican Curia, the Italian Bishops Conference, and the various dioceses concerned.

Based on the revisions, a set of Normae was issued on 15 November 1984, which was accompanied in the next year, on 3 June 1985, by enabling legislation.

According to the agreement, the practice of having one bishop govern two separate dioceses at the same time, aeque personaliter, was abolished.