Vitus, whose name is sometimes rendered Guy or Guido, was a Christian martyr from Sicily. His surviving hagiography is pure legend. The dates of his actual life are unknown. He has for long been tied to the Sicilian martyrs Modestus and Crescentia but in the earliest sources it is clear that these were originally different traditions that later became combined. The figures of Modestus and Crescentia are probably fictitious.

The Fourteen Holy Helpers are a group of saints venerated together by Catholics because their intercession is believed to be particularly effective, especially against various diseases. This group of Nothelfer originated in the 14th century at first in the Rhineland, largely as a result of the epidemic that became known as the Black Death.