That seems to be the conclusion of at least one scholar, based on an exhibition now on display in Rome:

Three mysterious signatures on pages of parchment bound in leather and kept under lock and key may prove the theory that William Shakespeare was a secret Catholic who spent his “lost years” in Italy.

An exhibition at the Venerable English College, the seminary in Rome for English Catholic priests, has revealed cryptic names in its guest books for visiting pilgrims, suggesting that the playwright sought refuge there.

“Arthurus Stratfordus Wigomniensis” signed the book in 1585, while “Gulielmus Clerkue Stratfordiensis” arrived in 1589.

According to Father Andrew Headon, vice-rector of the college and organiser of the exhibition, the names can be deciphered as “[King] Arthur’s [compatriot] from Stratford [in the diocese] of Worcester” and “William the Clerk from Stratford”.

A third entry in 1587, “Shfordus Cestriensis”, may stand for “Sh[akespeare from Strat]ford [in the diocese] of Chester”, he said.

The entries fall within the playwright’s “missing years” between 1585, when he left Stratford abruptly, and 1592, when he began his career as playwright in London.

“There are several years which are unaccounted for in Shakespeare’s life,” Father Headon said, adding that it was very likely that the playwright had visited Rome and was a covert Catholic.

The “Shakespeare” entries are being kept in the college’s archive for security reasons but have been reproduced for the exhibition, which illustrates the history of the college from its origins as a medieval pilgrims’ hospice to a refuge for persecuted Catholics during the Reformation.

Set in the college’s extensive 14th-century crypt, the exhibition conveys the clandestine atmosphere of underground Catholicism, with its spies and priests’ bolt holes. It traces the secret journeys made by Catholics to Rome and by Jesuit priests from Rome to England “to defend their faith despite the risk of being caught, tortured and martyred”.

In a recent book, a German biographer of Shakespeare, Hildegard Hammerschmidt-Hummel, said that she had “come to the conclusion that Shakespeare was a Catholic and that his religion is the key to understanding his life and work”.

Professor Hammerschmidt-Hummel said that Shakespeare’s parents, friends and teachers were Catholics, as were some of his patrons, including the Earl of Southampton, who concealed Catholic priests at his country seat, Titchfield Abbey, and his London residence.

Further proof was his purchase of the eastern gatehouse at Blackfriars — a secret meeting place for fugitive Catholics — in London in 1613, she said.

Backers of the theory say that plays such as Romeo and Juliet and Measure for Measure are “rich in Catholic thought and rituals”, with positive depictions of priests and monks and invocations of the Virgin Mary.