In 1442, Rene of Anjou lost this title to the invading Alfonso the Magnanimous, who signed the Treaty of Gaeta, established Trastamara rule, and passed it on to his son, Ferdinand I. Skanderbeg pledged himself a vassal to a man with this title, who also temporarily reunified it with an island kingdom.
A man with this royal title had his enemies embalmed in their familiar clothes and put on display in his "museum of mummies." Another man with this title continually extorted protection money from Pope Innocent VII and was named in honor of an ideal Hungarian ruler. Due to his illegitimacy, a man's claim on this non-Spanish title was temporarily opposed by his former tutor, Pope Callixtus III, and a war over it was fought when the childless queen (*) Joanna II disowned her adopted heir. In 1442, Rene of Anjou lost this title to the invading Alfonso the Magnanimous, who signed the Treaty of Gaeta, established Trastamara rule, and passed it on to his son, Ferdinand I. Skanderbeg pledged himself a vassal to a man with this title, who also temporarily reunified it with an island kingdom. For 10 points, what title was held by rulers whose domain formed part of the Kingdom of Two Sicilies?
A man with this royal title had his enemies embalmed in their familiar clothes and put on display in his "museum of mummies."
King of Naples [or Queen of Naples; or any sort of ruler of Naples;  accept "Sicily and Naples" for "Naples"; prompt on Two Sicilies for "Naples"; do NOT accept or prompt on "King of Sicily"Â—while Naples' kings claimed to have this title, that is categorically not how historians refer to them]