The Kingdom of Sicily was the Norman state founded in 1130 that fused Latin, Greek and Arab cultures, threatened Byzantium for two centuries, and lost its island in the Sicilian Vespers of 1282.
The Kingdom of Sicily was created in 1130 when Roger II united the Norman conquests in Sicily and southern Italy into a single monarchy, with the island — recently taken from its Muslim rulers — as its centre.
It was the wealthiest and most sophisticated state in twelfth-century Europe and the strangest: a Norman dynasty ruling Greek Orthodox and Arabic-speaking Muslim subjects, with an administration that worked in three languages and a court that borrowed from all of them.
For the Byzantine Empire it was a persistent western threat. Norman armies crossed the Adriatic repeatedly — Robert Guiscard nearly broke the empire in 1081, and Manfred sent the German troops who fought at Pelagonia in 1259.
Sicily had been Muslim for two centuries when the Norman adventurers Robert Guiscard and his brother Roger took it between 1061 and 1091, and southern Italy was largely Greek Orthodox and had been Byzantine until the same decade.
What the Normans built on that inheritance was genuinely unusual. The royal administration used Latin, Greek and Arabic; the fleet was commanded by a Greek with the Arabic-derived title of ammiratus, from which "admiral" comes; and the geographer al-Idrisi made his world map at Roger II's court.
The buildings say it best. The Cappella Palatina has Byzantine mosaics under an Arab honeycomb ceiling in a Latin chapel; the cathedral at Monreale and the Martorana in Palermo are the same synthesis. It did not survive the twelfth century intact — the Muslim population was later deported to Lucera — but while it lasted there was nothing like it.
Roger II (1130–1154) created the kingdom, codified its law, and made it a naval power that raided the Byzantine Empire and North Africa.
William I and William II held it through the twelfth century; the male line failed, and through marriage it passed to the Hohenstaufen. Frederick II (1198–1250) — king of Sicily, king of Germany, Holy Roman Emperor — governed it as the base of his power and the place he most wanted to be.
Manfred (1258–1266), his illegitimate son, sent the troops that fought at Pelagonia and married his daughter to Michael II of Epirus. Charles of Anjou (1266–1285) destroyed and replaced him, and then spent fifteen years preparing to conquer Constantinople.
The relationship was one of near-continuous hostility. Robert Guiscard invaded the Balkans in 1081 and beat Alexios I at Dyrrhachium; Roger II's fleets sacked Corinth and Thebes in 1147 and carried off the silk workers to Palermo; Manfred held Corfu and the Epirote coast.
The most dangerous phase came last. Charles of Anjou, having taken the kingdom in 1266, assembled a coalition through the 1270s explicitly to restore the Latin Empire at Constantinople, with papal backing.
Michael VIII's response was the Union of Lyons in 1274, which removed the papal justification, and then — when a new pope restored it — money. Byzantine gold went to Peter III of Aragon and to the discontented Sicilian nobility.
Roger II governed through an administration inherited in working order from the people he had conquered, which is why the kingdom was rich when comparable Norman states were not.
The Assizes of Ariano, issued around 1140, asserted royal authority over feudal custom far more firmly than any contemporary western monarchy managed, and the fiscal machinery — the diwan, run in Arabic — was Fatimid in origin and unmatched in Latin Europe.
Frederick II took it further with the Constitutions of Melfi in 1231, a code that treated the kingdom as a single legal jurisdiction under the crown. Historians have called the result the first modern state in Europe, which overstates it; what is not overstated is that Sicily was administered while its neighbours were merely ruled.
On Easter Monday 1282 the population of Palermo rose against the French garrison, in a massacre that spread across the island within weeks. Peter III of Aragon landed in August and took Sicily.
Charles's fleet, assembled for Constantinople, was destroyed or diverted, and the invasion never sailed. Michael VIII wrote that if he said God had freed the Sicilians through him, he would only be telling the truth — and he was.
The kingdom split permanently: Aragon held the island, the Angevins held the mainland from Naples, and the two fought for twenty years. The Byzantine Empire got another century and a half from it.