Alfonso transfers his court to Naples in…
1443 CE
Alfonso transfers his court to Naples in 1443 and, gaining papal recognition as King of Aragon, Sicily, and Naples, Alfonso uses the name “the Two Sicilies” ((Utraque Sicilia, literally "both Sicilies") to refer to the jointly-ruled kingdoms of Sicily and Naples.
The two states had functioned as separate realms since the War of the Sicilian Vespers in 1282.