The Two Sicilies
Students of history - and indeed other subjects - may from time to time be surprised to hear of the Kingdom of the Two Sicilies. (There is only one island of that name in Europe; three homonyms exist in the United States, presumably named after the Italian original.) The island has a complex history. The Norman Count Roger I (1071–1101) held territory on the nearest part of the mainland, in Calabria and Apulia, and his son Roger (1105–1154) became, as Roger II, King of Sicily. (Although he was the second Count of Sicily of his name, he was the first King Roger of Sicily.) When he conquered the Duchy of Naples in 1137, the two territories were ruled as the Kingdom of Sicily. They were divided in 1282, Naples being allocated to the French Angevin dynasty and Sicily to the Spanish Aragones dynasty. In 1442, Alfonso I (1416–1458) of Sicily conquered Naples, and ruled as King of Aragon, Sicily and Naples. The kingdoms were separate from then, until, after the Napoleonic wars, in 1816, Ferdinand, who "had been Ferdinand III of Sicily but Ferdinand IV of Naples, which people found complicated and confusing" (Norwich, John Julius (2015) Sicily: An Island at the Crossroads of History), formally assumed the title of Ferdinand I of the Two Sicilies. The Congress of Vienna (1814-5) had already "decided [...] that the Two Sicilies should continue as a single kingdom," regularizing a common expression owed in part to the fact that from 1282 Kings of Naples continued to call themselves 'King of Sicily' (or 'King of the Two Sicilies' [rex Utriusque Siciliae]), while the Kings who ruled in the island naturally continued to call themselves 'King of Sicily'.
- It is also true that "In 1764 ... there had arrived a new [British] Envoy Extraordinary to the Kingdom of the Two Sicilies, Sir William Hamilton." So it is possibly British diplomatic vocabulary that led to the usage adopted by the Congress.
- The Kingdom of the Two Sicilies came to an end with the Risorgimento. After Garibaldi had taken Sicily and defeated the Neapolitan army in 1860, he declared both kingdoms annexed to the Kingdom of Sardinia [and Piedmont] after overwhelming votes in favour in plebiscites; in 1861, this became the kingdom of Italy, under King Vittorio Emmanuele (Victor Emmanuel).