But locals say the man nicknamed "Good Pope John" for his down-to-earth personality -- similar to that of Pope Francis -- should be remembered as a driving force behind reforms in Catholicism still relevant today.
Born in Sotto il Monte in the foothills of the Alps in 1881, Angelo Roncalli was elected pope in 1958 and reigned as John XXIII until his death in 1963.
The loyalty here is so strong the town of 4,000 people changed its name to "Sotto Il Monte Giovanni XXIII".
And preparations for a feast on April 27 -- when John XXIII will be made a saint along with a more famous successor, John Paul II -- are in full swing.
Benigna, a pilgrim from a nearby village visiting John XXIII's hometown with a group of fellow pensioners, said she was impressed by the resemblance between the reformist pope and the current pontiff.
"They have that humility in common, him and Francis, that love with which they talk to us. They are similar!" she said.
John XXIII was beatified in 2000 by John Paul II, leaving him one step from sainthood, and Francis decided in September last year on the full canonisation.
"We rang the bells for half an hour! People asked why. I knew the news a little bit before it was announced in the press," said the local parish priest, Claudio Dolcini.
"Then at Sunday mass, we prayed and people were delighted, they applauded. There was a great atmosphere of celebration," Dolcini said.
Francis sped up the canonisation since John XXIII has only one supposed miracle to his name while the traditional procedure requires at least two miracles.
The surprise came even as "we found two particularly interesting cases of miracles that we were researching and preparing to submit to Rome," Dolcini said smiling.
- 'Closed' in Vatican -
The town in 2012 set up a Pilgrim House that offers tours for visitors including to the house where he was born and the humble chapel where he said he received a divine vocation to become a priest.
"His mother always brought him here to this chapel," said Pina, the custodian.
"They prayed to the Madonna. This was his favourite place in the world, this little chapel even though there's basically nothing here," she said.
The quiet town is preparing for an influx of up to 25,000 people and giant 3D screens will be set up to follow the canonisation mass celebrated by Francis.
The event will be modest compared to the celebrations in Rome, where numbers are expected to be between several hundreds of thousands of people and millions.
But the event is likely to give a new dimension to a following for John XXIII that has remained rather discreet until now -- or at least that is the hope at Sotto Il Monte.
"The figure of Pope John really has to be discovered," said Gimmy Schiavi, director of Pilgrim House.
"He is known as the 'Good Pope'. We wanted to elevate the debate a little, make known his previous works, what he did abroad, tackle more complex themes."
"He began a process of change that all his successors, and especially Francis, have followed," he said, referring to the Second Vatican Council started under John XXIII in 1962 which modernised the Church.
Dolcini agreed saying: "He unleashed a revolution -- in the good sense of the word!"
Marco Roncalli, the pope's great-nephew and the author of three biographies of the future saint, said the reality of John XXIII was "more complex" than the popular image.
"He was not just a good parish priest but also a statesman, who as Francis said was a great guide and was himself guided by God," he said.
Like Francis today, John XXIII "needed to be with people", he said.
"He used to tell my grandfather, his youngest brother, that he felt a bit like a prisoner in the Vatican in a closed atmosphere. I think he really suffered."