A powerful Sicilian fleet had been built up under several admirals, or "emirs", of whom the greatest is George of Antioch, formerly in the service of the Muslim prince of Mahdia.

Mainly thanks to him, a series of conquests have been made on the African coast from 1135.

Taking advantage of internal strife and of a famine episode, George had captured Tripoli in 1146 and Cape Bona in 1148.

The Zirids, forced to abandon al-Qayrawan, hadve retreated to Mahdiyah, but their shattered state is not long able to survive the coastal attacks by Sicilian Normans and finally falls to them in 1148.

Sicilian Normans, after defeating the Zirids in 1148, occupy the independent city-state of Sfax, founded in 849 on the ruins of Taparura and Thaena.

(These North African conquests will be lost in the reign of Roger's successor William and will never form an integral part of the kingdom.)

The death of Alfonso I, called the Battler or the Warrior, the king of Aragón and Navarre from 1104 until his death in 1134, had led to a succession crisis in Aragon, and the nobles of Navarre had taken advantage to reestablish an independent monarchy, crowning a grandnephew (through an illegitimate brother) of the assassinated Sancho IV.

King García Ramírez, the grandson of Rodrigo Díaz, better known as El Cid, is the son of Ramiro Sánchez of Monzón and Cristina Rodríguez Díaz de Vivar.

Sometime after 1130, but before his succession, García had married Marguerite de l'Aigle, who has borne him a son and successor, Sancho VI, as well as two daughters who have each married kings: the elder, Blanca, born after 1133, has married Sancho III of Castile, while the younger, Margaret, named after her mother, has married William I of Sicily.

García's relationship with his first queen was, however, shaky.

She took on many lovers and showed favoritism to her French relatives.

She had borne a second son named Rodrigo, whom her husband has refused to recognize as his own.

On 24 June 1144, in León, García had married Urraca, called "La Asturiana" (the Asturian), illegitimate daughter of Alfonso VII by Guntroda Pérez, to strengthen his relationship with his overlord.

An ally of Castile in the Reconquista, García has been instrumental in the conquest of Almería in 1147.

In 1146, he had occupied Tauste, which belonged to Aragon, and Alfonso had intervened to mediate a peace between the two kingdoms.

By his marriage to Urraca, García had also become a brother-in-law of Raymond Berengar IV, with whom he had confirmed a peace treaty in 1149.

The count has been promised to García's daughter Blanca while already engaged to Petronilla of Aragon, but García dies on November 21, 1150 in Lorca, near Estella, before the marriage can be carried out.

Buried in the cathedral of Santa María in Pamplona, García is succeeded by his eldest son, leaving one daughter by Urraca: Sancha, who is to marry Gaston V of Béarn.

He leaves a widow in the person of his third wife, Ganfreda López.

His successor, as Sancho VI, is the first to use the title "King of Navarre" as the sole designation of his kingdom, dropping Pamplona out of titular use.

The Greeks find it hard to to accept the fact that their empire, centered on Constantinople, might soon become simply one among a number of Christian principalities.

Emperor Manuel had retained the personal friendship and the alliance of the German emperor Conrad III against the Normans and even planned a joint Greek-German campaign against them in Italy, but after 1152, no such cooperation has been possible with Conrad's successor.

To Frederick, the alliance between the Roman Empire of Germany and what he calls “the kingdom of the Greeks” is not one between equals.

After Roger II of Sicily dies at fifty-eight in 1154, Manuel launches a vain invasion of the Norman kingdom on his own account, in support of the rebel towns and the barons, who have rallied around Robert III of Loritello, the cousin of William, Roger’s fourth but oldest surviving son and thus Sicily’s new king.

Roger II of Sicily dies at Palermo on February 26, 1154 and is buried in the Cathedral of Palermo.

He is succeeded by his fourth son, William, who had grown up with little expectation of ruling.

The deaths of his three older brothers Roger, Tancred, and Alfonso between 1138 and 1148 had changed matters, though when his father dies William is still not well-prepared to take his place.

On assuming power, William keeps the administration that had guided his father's rule for his final years.

Only the Englishman Thomas Brun is removed, and the chancellor Maio of Bari is promoted.

The real power in the kingdom is at first exercised by Maio, a man of low birth, whose title ammiratus ammiratorum is the highest in the realm.

Maio continues Roger's policy of excluding the nobles from the administration, and seeks also to curtail the liberties of the towns.

The barons, always chafing against the royal power, are encouraged to revolt by Pope Adrian IV, whose recognition William has not yet sought, by the East Roman Emperor Manuel I Komnenos, and by the Holy Roman Emperor Frederick I, who had had canceled his plan to invade Sicily when Roger died.

Continuing his father’s ambitions, William offers peace to Manuel, is refused, and then makes peace with Venice, thus depriving Constantinople of a war fleet.

Maio is not popular with the baronage and supports the immigration of Western Europeans, Roman Catholics all, to increase the influence of this church, which is initially his largest supporter.

The chief baronial opponent to Maio is, at first, Robert de Bassonville, the count of Loritello and cousin to the king.

He resents Maio's rise and his own cousin helps the imperial forces to recover Bari, …

…Trani, …

…Giovinazzo, …

…Andria, …

…and Taranto by the end of 1155, and to …