VATICAN CITY (EWTN News/CNA) — An unprecedented 2012 exhibition of around 100 historical documents from the Vatican’s Secret Archives will include items from Pope Pius XII’s wartime papacy and Galileo’s trial.

Cardinal Raffaele Farina, the Vatican’s archivist and librarian, explained the importance of the exhibit to the media on July 5: “Ancient pontifical documents of great importance, as well as letters concerning significant aspects of the life of the Church in the world, will be leaving the Vatican for the first time.”

Entitled “Lux in Arcana: The Vatican Secret Archives Unveiled,” the exhibition will run from February to September next year at Rome’s Capitoline Museums. It marks the 400th anniversary of the archive’s inception.

The collection will include notable items, such as Pope Gregory VII’s “Dictatus Papae,” which outlines the powers of the Roman pontiff; a 1530 letter from members of the English Parliament on King Henry VIII’s marital situation; minutes from the 1633 trial of Galileo Galilei, signed by the astronomer himself; and an 1887 letter from Native Americans to Pope Leo XIII, written on birch bark.

But what raised the most eyebrows at the press conference was the announcement that documents related to the wartime activities of Pope Pius XII will also be on display.

Critics of Pope Pius accuse him of not taking a stand against the Nazis’ persecution of the Jews, a charge strongly denied by his supporters, who call it a “black legend.”

“What we’re talking about today is an important first — a double first,” explained Umberto Broccoli, who is in charge of cultural heritage for the city of Rome.

“The Pope’s personal secrets are revealed: The veil is taken away from them after years of being reserved only for the watchful eyes of scholars and experts and are now to be shown to the public.

“But it is also the first time that the Vatican will be making a loan to a museum in Rome.”

The Secret Archives were created in 1612 by Pope Paul V. They remained closed until 1881, when Pope Leo XIII opened them to academic researchers. The archives contain 52 miles of shelves holding over 35,000 historical texts and documents.

The word “secret” actually has the more ancient meaning of “private” rather than modern definition of “hidden” or “mysterious.” This denotes that the archives are directly under the care of the Pope and not a department of the Roman Curia.

“It is a courageous gesture on the part of the Holy See to organize an exhibition at this level, at the same time agreeing to let these precious documents leave the Vatican,” said Rome’s Mayor Giovanni Alemanno.“Lux Arcana is an opportunity to recount to both Romans and pilgrims the extraordinary adventure of man.”