At the end of the third century, during the last persecution against Christians by Emperor Diocletian, Christina, twelve-year-old daughter of pagan Bolsena prefect, was subjected to torture. Just converted to Christianity, the girl miracolously managed to survive being tortured, her executioners dying in her place. Christina was then thrown into the lake tied by the neck to a stone, but instead of being dragged to the bottom, she remained afloat, the stone even bringing her back to the shore, where her father, appalled, died seized by an illness. Finally, after having been subjected to every kind of atrocious torture and mutilation, Christina died July 24, 304, her heart pierced by arrows.

In the summer of 1263, Bohemian priest Peter of Prague, upon returning from his pilgrimage to Rome, was witness to the so-called Miracle of Bolsena, that inspired Pope Urban IV to create the feast of Corpus Christi.