The Graeco-Roman name Dionysius, deriving from the name of the Thracian god Dionysus, was exceedingly common, and many ancient people, famous and otherwise, bore it. It remains a common name today in the form Dennis (Denys, Denis, Denise). The modern Greek form of the name is Dionysios or Dionysis. The Spanish form of the name is Dionisio. The Italian form of the name is Dionigi.
Read more about Dionysius: People Named Dionysius