The Black Army (Hungarian: Fekete sereg, pronounced [ˈfɛkɛtɛ ˈʃɛrɛɡ], Latin: Legio Nigra), also called the Black Legion/Regiment – possibly after their black armor panoply – is a common name given to the military forces serving under the reign of King Matthias Corvinus of Hungary. The ancestor and core of this early standing mercenary army appeared in the era of his father John Hunyadi in the early 1440s. The idea of the professional standing mercenary army came from Matthias' juvenile readings about the life of Julius Caesar.