The Bell of the Fallen was solemnly inaugurated on 4 October 1925 in the presence of the King, Victor Emmanuel III.
In the days leading up to the inauguration, the preparations intensified, as did the various controversies which added to the numerous organisational issues to be resolved, and which Don Rossaro duly noted in his diary:
«"19 September: At 10 o'clock, the Bell is moved for the first time. Its perfect functioning is admired.

"19 September: At 10 o'clock, the Bell is moved.

21 September: Prefect Guadagnini informs me that the King does not want the 4th October, and therefore asks that the date is changed - I mention that the date was fixed a long time ago - and for some time the King has agreed to it - that I chose the date in honour of S. Fancis, the saint of universal brotherhood - that I prefer to cancel...rather than change this highly significant date - Several days later, the Prefect announces that the 4th October is agreed. I later learned, privately, that the King felt bad, and kept his word as“word of the king”. But meanwhile I got what I dreamed of: the date, 4th October, and the presence of HRH the King. I would have chosen to give that up!!!

2 October: I heard the first ringing. It was 6 pm.

2 October: I heard the first ringing. It was 6 pm. I was returning from Trento with Countess Cattaneo [a sponsor of the Bell]. As we came out of the station I heard the "first ringing" of the Bell! Joy? Disappointment? Emotion? Torment? I don't know. [Don Rossaro is certainly very tense and exhausted].

33 October: Work is proceeding at a furious pace at the Castle. The city is extremely excited . The weather is good.

The evening before the King's arrival saw an extraordinary illumination of the castle, the civic tower, the square and Corso Rosmini, and for the occasion the special lamps designed by Futurist painter Fortunato Depero for the baptism of the Bell (24 May)were once again displayed on the Cassa di Risparmio building; to this day, these are often placed on the balconies of the bank on special occasions. The following day, the King was met at the railway station by local and national authorities, including the Honourable Celesia di Vegliasco, Under-Secretary of State for Communications, sent to represent the Government. At the Town Hall the King received the official welcome of the city by the Interim Commissioner Defrancesco, then watched from the balcony of the Podestà palace the impressive procession of veterans, soldiers and the injured from all over Italy, led by representatives of the army and the national guard.

SAfter this, the King was taken to the Malipiero Bastion of the castle to witness the inauguration ceremony of the Bell and listen to its first ringing. In addition to the sponsors and numerous generals, the audience included many foreign delegates such as the Consuls of Britain, the United States, Czechoslovakia, France and Belgium. The monarch attended Holy Mass, officiated by the Prince-Bishop of Trento, Monsignor Celestino Endrici; then, following speeches by Don Rossaro and the Honourable Celesia, put his concluding signature to a copy of the Golden Register of the Bell, the document listing the names of the 12,000 donors who contributed to the casting of the great bronze by raising approximately 300,000 lire. This copy was placed in a special alcove in the place where on 24 March the previous year, Prince Umberto had laid the foundation stone for the Bell's supporting structure.

The most eagerly-awaited and solemn moment - the Bell's first ringing - was described very well by Don Rossaro in his diary: "At the first stroke [of the Bell] the King stood and saluted. Then he looked at me. General Pecori Giraldi affectionately brought me towards the King, despite my resistance. The King said: "Good, good, Reverend. It's truly a great monument", and, turning to Minister Celesia, "He should be made a Commander". Quite frankly, I was not thinking of such things, and I made a gesture of thanks. I was thinking something else entirely! Frankly, the sound was not good, and every stroke pierced my heart like a poisoned blade. Even in the midst of such joy, I was not spared the poison. Even the joy must be poisoned, and - calm but troubled, discouraged but strong - as they all applauded, I was thinking: "I'll have it recast!"...the Bell sounded wrong, it was like iron. At one point General Pecori Giraldi (who was a bit deaf), to the right of the King, said loudly "That Bell's hoarse". I was to the left of the King who, perhaps to disguise the inappropriate observation, made a sudden movement, as if to point at one of the doves which were fluttering about, but I understood, and said directly, almost in answer to the general's comment: Your Majesty, the Bell will be recast"; "You have the fortitude?" he replied. "Your Majesty", I answered, "I hope you can be present... next time". "I hope so" [the King replied] and smiled! At the sound of the Bell which, although beautifully made from the aesthetic point of view, had a somewhat unpleasant tone, hundreds of doves were released, and flew into the air at the same time as the cannon shots and cries of Salve that accompany all of Italy's bells. This was followed by the singing of the official anthem of the Bell, while aeroplanes flew over the castle among the noise of artillery. Don Rossaro commented further on the ceremony, adding to his notes a criticism of the king:

"A strident note! - On the bastion, in the presence of the King and all the authorities and sponsors of the Bell of the Fallen, the Bishop celebrated Holy Mass, right at the foot of Maria Dolens.

The King's behaviour during the Mass was impolite and deplored by all: he spent the time chatting and pestering those around him, who in full sight of the crowd, found themselves visibly uneasy...he commented on the mountains of Biaena, Baldo and Zugna, asking for information about the war events that took place there. The Bishop was extremely annoyed".

At the conclusion of the ceremony at the castle, the King visited the Museum and then paid homage at the tombs of the fallen at Castel Dante cemetery. He then returned to the city and left Rovereto on the special train that awaited him at the station. The festivities for the Bell continued in the afternoon with a performance at the municipal theatre in the presence of Under-Secretary Celesia and other leading figures; during the show the anthem of the Bell was sung again, in addition to the Song for the Fallen, written by Riccardo Zandonai. That evening, a bonfire and fireworks display accompanied the first evening ringing "at the hour of nightfall", as established in the Statute of the Bell.

Even in these circumstances, Don Rossaro did not attend the official banquet: "I won't go to the official banquet. I prefer to stay at home, surrounded by my family", he wrote in his diary entry for this memorable day. And similarly, his reticent nature also led him to oppose the placing of a stone in his honour on the facade of the Bell room, as a token of thanks by Italian mothers.