The Viking history of Sicily begins with the invasion of the Normans — a people of Norwegian origin who had settled in Normandy, northern France — led by the Norman Jarl Rogeirr (Count Roger de Hauteville) and his brother Robert. The Norman monk Geoffrey Malaterra, in his De rebus gestis Rogerii Calabriae et Siciliae comitis et Roberti Guiscardi ducis fratris eius (a chronicle of the Norman origins in Italy), described Roger as follows:  

"He was a very handsome young man, tall and elegantly proportioned, quick-witted, wise in counsel, and farsighted in handling affairs. He always maintained a friendly and cheerful character. He possessed great physical strength and courage in battle. Thanks to these qualities, he quickly won the favor of all." 

In 1061, the two brothers arrived in Messina, where they encountered no resistance from the Arabs and advanced as far as Enna, seizing control of eastern Sicily from the Saracens. Roger achieved another major victory in 1063 at the Battle of Cerami, where — according to exaggerated chronicles — he and his nephew, with just 136 knights, defeated 45,000 Muslims.  

The Norman expansion continued, leading to the conquest of Bari in 1070 and Palermo in 1072, the latter with the assistance of Robert and the surrender of the city's keys by the Saracens—solidifying Norman rule over Sicily. In 1071, Robert appointed Rogeirr as the first Count of Sicily, after which he also conquered Taormina.  

Following Robert’s death in 1085, Roger became the sole ruler. In 1086, he expelled the Arabs from Syracuse and received the Pope’s blessing in 1090. By 1091, after 30 years of battles and the conquest of the island’s last remaining cities, Roger had full control of Sicily, earning the title of Grand Count of Sicily.  

As a ruler, he surrounded himself with Norman nobles, proving to be both a skilled military commander and a shrewd political strategist. He laid the foundations for a feudal kingdom, limiting aristocratic power and strengthening his own rule. He built numerous churches and promoted the economic revitalization and repopulation of the island. Roger died in 1101, and the Norman Hauteville dynasty ruled Sicily until 1197.