Caesar’s crossing of the Rubicon in January 49 BC changed the Roman world beyond recognition. During the years of his dictatorship, the coinage of Caesar’s empire underwent profound changes, too, on various levels. This paper provides a comprehensive analysis of Caesar’s various monetary reforms, in the context of his economic policies. Furthermore, it explores the modifications to the production structures of coins that Caesar implemented, as well as the revolution in coin design that took place at the end of his reign: his portrait was the first of a living Roman ever to appear on issues struck at the urban mint. All of these changes had a profound impact on the monetary economy of subsequent centuries, and Julius Caesar may be termed the ‘father of Roman imperial coinage’.