It's an incident that has stained the Vatican for 160 years: a six-year-old Jewish boy taken from his family by papal police and brought to Rome to be raised Catholic after church authorities learned his housekeeper had secretly had him baptised.
Now the case has reared its head again, with new evidence that memoirs the boy wrote as an adult were altered to take the edge off his anti-Semitic views and enhance details favourable to the Catholic Church.
The Associated Press has confirmed findings by Brown University historian David Kertzer that Edgardo Mortara's memoirs were changed in ways big and small when they were translated from the original Spanish into Italian and published to great fanfare by Italy's Mondadori house in 2005. AP found the Spanish text in a religious order's archive this week.
The alterations do not significantly change the overall thrust of Mortara's oft-stated gratitude to the "saint" Pope Pius IX for having saved his soul by removing him from his Jewish family to raise him Catholic. But they do indicate that the tale - already subjected to over a century of revisions to suit various interests - has been recrafted again.
The changes, Kertzer told AP, "were clearly made with certain narrative purposes, to craft a narrative that was more in line with what the conservatives in the church would like to present as what had happened in the story".
That story began when Inquisition police took six-year-old Edgardo from his home in Bologna on June 24, 1858. The reason? The Mortaras' 16-year-old Catholic housekeeper had had Edgardo secretly baptised when he fell ill as an infant, fearing for his soul if he died.
Mortara survived, and when word reached church authorities that a baptised Catholic was living in a Jewish home, the Inquisition ordered his sequester under laws requiring Catholics be raised as such.
Pius took Edgardo under his wing, and the Jewish-born boy eventually became a Catholic priest, taking Pius as his priestly name. He died in 1940 in Belgium.
While such sequesters, as they were known, were not unheard of, the kidnapping became an international scandal and contributed to the anti-clerical sentiment sweeping across Europe.
In Italy, the cause emboldened the liberalising Risorgimiento forces who unified the country and brought about the collapse of the papal states through which the pope had controlled a swath of central Italy.
The 2017 publication of the English version of Mortara's memoir - which includes all the alterations contained in the Italian - has cast a new spotlight on the case, just as Steven Spielberg is developing a film based on Kertzer's 1997 book The Kidnapping of Edgardo Mortara, and Pius' case for sainthood is pressing ahead.
In a recent article in The Atlantic magazine, Kertzer outlined several inconsistencies between the Spanish version of Mortara's memoir and the Italian translation published by leading papal author Vittorio Messori in 2005 and titled, Me the Jewish Boy Kidnapped by Pius IX: The unpublished memoirs of the protagonist of the Mortara case.
Kertzer and Messori have feuded for years about the Mortara affair.
The memoir in question, written in Spanish because Mortara was living in Spain at the time, is actually a contemporary, typed-up version of a handwritten one Mortara purportedly penned a century ago. The location of the handwritten text is unknown.
AP this week found the typed-up Spanish version in the historic archives of the religious order Mortara joined, alongside his handwritten journals and shelf upon shelf of dusty tomes of centuries-old church documents.
Among other things, AP found that anti-Semitic comments contained in the original Spanish had been removed from the Messori translation, including a reference to Mortara having "always professed an inexpressible horror" towards Jews.
Mortara's great-great niece, Elena Mortara, said in an interview that the change was evidence of an effort to erase the anti-Jewish indoctrination her ancestor received from the Catholic teachers who raised and educated him.
During an interview at her home, Mortara spoke of her family's pain, which has been recounted from generation to generation, but also pride over the episode's historical relevance.
"We knew that the family had fought for civil rights that would become civil rights for all citizens," said Mortara, who wrote about the global significance of the case in a 2015 book.
Elena Mortara, who led a public protest by the family and Italy's Jewish community when St John Paul II beatified Pius in 2000, dismissed the value of even the Spanish version of the memoir as a document. She noted that it was written in the impersonal third person and typed up by someone else, and differs greatly in tone from Mortara's handwritten journals, "where he shows all the conflicts within him, all the psychological conflicts, the drama of his soul".
Messori, for his part, insisted in a series of emails to AP that he worked from the original Spanish text and that a translator had faithfully translated it. He blamed any changes in the published version on editors at Mondadori, the Italian publishing house.
Australian Associated Press