Osanna confided these things in her biographer and "spiritual son," the Olivetan monk, Dom Jerome of Mount Olivet, as well as the fact that for years, she subsisted on practically no food at all.

When she died in Mantua on 18 June 1505, all the members of the nobility and clergy attended her funeral, as her body was taken in procession to the Church of St. Dominic, where it was enshrined.

[8] Her confidant, Dom Jerome (Italian: Girolamo de Monte Oliveto), wrote a vita (biography) of her life in 1507, very shortly after her death.

[7] According to Father Benedict Ashley, these letters express an "intense and constant physical and inner suffering" made bearable only by "sublime experiences of union with God which [Osanna] cannot describe except in broken and inadequate language."

[7] In a response to a request by the Marchesa Isabella d'Este while on a visit to Rome, through a papal brief of 8 January 1515 Leo X authorised the celebration of her feast day in the City of Mantua.

Her local cultus was confirmed by Pope Innocent XII with a Papal bull of 24 November 1694, and extended to the whole of the Dominican Order two months later.

[5][9] The content of the literary corpus of the Blessed Osanna ranges from mystical reflection to considerations on contemporary social and political questions.