Born in San Gemini, in Umbria, on 20 December 1885, to Angelo Galeazzi and Degna Gentili, he moved to Turin in 1898 to begin his religious studies at the Little House of Divine Providence, thanks to the intervention of Cesare Boccanera, Bishop of Narni.

[2] During his long episcopate, the Diocese of Grosseto underwent significant transformation and innovation, thanks to numerous pastoral initiatives and the extensive construction of churches and diocesan structures.

On 9 April of the same year, marking the eight-hundredth anniversary of the relocation of the Rusellae episcopal seat, he established a new parish in Roselle dedicated to the Immaculate Conception.

[3] In 1943, Bishop Galeazzi decided to lease the summer residence of the diocesan seminary in Roccatederighi to the fascist Italian Social Republic (RSI) to be used as a concentration camp for Jewish detainees.

The lease agreement, signed by the bishop and the Public Security Marshal Gaetano Rizziello, director of the camp, stated: "Due to wartime emergencies" and "as a special tribute to the new Government", the Curia leased the summer seminary in Roccatederighi for the establishment of the "Jewish concentration camp" at a monthly rent of 5,000 lire, along with the services of five nuns for "kitchen, pantry, wardrobe, infirmary, and maintaining order in the women's dormitories."

[1] On 1 January 1960, he established four new parishes in Grosseto: the Holy Crucifix for the suburb of Porta Vecchia, St. Lucia for the neighborhood of Barbanella, St. Charles Borromeo for Principina Terra, and St. Vincent de Paul for Casotto dei Pescatori.