However, canonization as an ecclesiastical procedure was not outlined until the 11th century with the aim of seeking to define those Christians who would deserve the universal reverence of the Church, thus avoiding confusion between local churches and seeking that the virtues of the deceased were fully proven.
[1] In the 17th century, Urban VIII began to make pontifical declarations of canonization through papal bulls, the first canonized saints being Philip Neri, Ignatius of Loyola, and Francis Xavier, and in other bulls Urban would decree the beatification of other Servants of God.
Similarly, in 1634, through the bull Caelestis Hierusalem cives, he established such powers of beatification and canonization as exclusive to the Holy See.
[2] In the first half of the 18th century, Bishop Prospero Lambertini, before being elected as pope under the name of Benedict XIV, published his major liturgical work entitled De servorum Dei beatificatione et de beatorum canonizatione, where he expounded the procedure of equivalent canonization and described the possibility of establishing public veneration for a person whose reputation for holiness and heroic virtue has long been proven by tradition and for whom there was already a prior veneration in the Church.
Various saints have been included in the martyrology in this way, including Romuald, Norbert of Xanten, Bruno of Cologne, Peter Nolasco, Raymond Nonnatus, John of Matha, Felix of Valois, Margaret of Scotland, Stephen I of Hungary, and Pope Gregory VII.