|First appearance||Spartacus: Morituri|
|Last appearance||Spartacus: Morituri|
|Relationships||Mantilus (Slave, deceased)|
Quintus Lentulus Batiatus (Rival, deceased)
Marcus Licinius Crassus (Former Patron)
|Status||Unknown (presumed deceased)|
Leonidas Hieronymus is a Greek nobleman from Sicilia who made his fortune serving as trader and money changer in Ephesus and Pergamon. He seeks permanent residence in Capua where he has started his own Ludus. He sees his biggest rival as Batiatus, whose gladiators include the last two champions of Capua.
Hieronymus is a large man with brown skin and olive-brown eyes. Like most Greeks, he is bearded. He wears gold earrings and a woolen peplos, despite the warm weather of Capua.
Hieronymus is a proud man, who seems to play as friend only to gain what he wants. He is willing to throw his money around to keep face and to show his power and wealth.
Hieronymus is first seen alongside his body slave, Mantilus, at the home of the slaver, Albanus. while there, he outbids Batiatus for the ownership of Athenais. Afterward, he gives her away as a gift since he prefers boys. Hieronymus later sends his slave Mantilus to have Batiatus' Ludus' water source poisoned to weaken his gladiators before an upcoming games. Eventually, Spartacus discovers Hieronymus' actions and informs Batiatus, who instead of exposing him sets up a wager where whoever’s graduators shall prevail in an upcoming games shall gain all the possessions of the other, knowing full well that Hieronymus’ gladiators no longer hold advantage. Batiatus also uses his own Ludus’ water to poison him at the games causing him to hallucinate and believe Crassus has the head of a wolf. Hieronymus' behavior in the pulvinus, and the reveling of his scheme, causes Crassus to end his patronage of Hieronymus before kicking him in the ribs as he cowered in a corner. After the games, at Batiatus’ villa, news arrives that Hieronymus’s house caught fire with himself most likely trapped inside, with the probable suspect being Crassus in response to the dishonor Hieronymus’ deception brought him.
- Hieronymus may have possessed Roman citizenship if he was a Lanista in the Roman Republic and being from the island of Sicilia. The Social War of 91-88 BC occurred sixteen years prior to the Third Servile War. In the aftermath of the former, virtually all Socii (allied states) in Italy, be they of Latin, Samnite, Etruscan or Greek ethnicity, were universally granted Roman citizenship and suffrage.