Charles Martel, Duke of Calabria (Italian: Carlo Martello) is a name and title shared by two short-lived heirs to the throne of the Kingdom of Naples.
Charles Martel (13 April 1327 – 21 April 1327), was the third child and first son of Charles, Duke of Calabria, heir of Robert, King of Naples and Yolande of Aragon and his wife Marie of Valois, a niece of King Philip IV le bel of France.
The newborn prince, his sister and his father were the only living, legitimate, male-line descendants of his paternal grandfather, Robert, King of Naples.
Joanna eventually became Queen of Naples — a younger sister to the Duke was born after his father died, in 1329.
The newborn Duke of Calabria and his mother and aunt were the only living, royal, legitimate descendants of his paternal great-grandfather, Robert, King of Naples.