11th century, the mainland southern Italian powers were hiring Norman mercenaries, who were Christian descendants of the Vikings; it was the Normans under Roger I (of the Hauteville dynasty) who conquered Sicily from the Muslims over a period of thirty years until finally controlling the entire island by 1091 as the County of Sicily. In 1130, Roger II founded the Norman Kingdom of Sicily as an independent state with its own Parliament, language, schooling, army and currency, while the Sicilian culture evolved distinct traditions, clothing, linguistic changes, cuisine and customs not found in mainland Italy. A great number of families from northern Italy began settling in Sicily during this time, with some of their descendants forming distinct communities that survive to the present day, such as the Lombards of Sicily. Other migrants arrived from southern Italy, as well as Normandy, southern France, England and other part of North Europe. The Siculo-Norman rule of the Hauteville dynasty continued until 1198, when Frederick II of Sicily, the son of a Siculo-Norman queen and a Swabian-German emperor ascended the throne. In fact, it was during the reign of this Hohenstaufen king Frederick II, that the poetic form known as a sonnet was invented by Giacomo da Lentini, the head Poet, Teacher and Notary of the Sicilian School for Poetry. Frederick II was also responsible for the Muslim settlement of Lucera. His descendants governed Sicily until the Papacy invited a French prince to take the throne, which led to a decade-and-a-half of French rule under Charles I of Sicily; he was later deposed in the War of the Sicilian Vespers against French rule, which put the daughter of Manfred of Sicily - Constance II and her husband Peter III of Aragon, a member of the House of Barcelona, on the throne. Their descendants ruled the Kingdom of Sicily until 1401. Following the Compromise of Caspe in 1412 the Sicilian throne passed to the Iberian monarchs from Aragon and Castile. Modern and contemporary history In 1735, the Spanish era ended when Charles V from the House of Bourbon was crowned king. For the better part of the next century-and-a-half, Sicily was in personal union with the other Southern Italian Kingdom of Naples, with the official residence located in Naples, under the Bourbon dynasty. After the Napoleonic Wars, King Ferdinand I, who had just recently been restored back to the throneship of Southern Italy in 1815,