List of Sicilian monarchs in the context of "Curia regis"

Philip II (21 May 1527 – 13 September 1598), sometimes known in Spain as Philip the Prudent (Spanish: Felipe el Prudente), was King of Spain from 1556, King of Portugal from 1580, and King of Naples and Sicily from 1554 until his death in 1598. He was also jure uxoris King of England and Ireland from his marriage to Queen Mary I in 1554 until her death in 1558. Further, he was Duke of Milan from 1540. From 1555, he was Lord of the Seventeen Provinces of the Netherlands.

The son of Emperor Charles V and Isabella of Portugal, Philip inherited his father's Spanish Empire in 1556, and succeeded to the Portuguese throne in 1580 following a dynastic crisis, forming the Iberian Union. The Spanish conquests of the Inca Empire and of the Philippines, named in his honour by Ruy López de Villalobos, were completed during his reign. He finished building the royal palace El Escorial in 1584. Under Philip II, Spain reached the height of its influence and power, advancing into the Spanish Golden Age, and ruled territories in every continent then known to Europeans. Deeply devout, Philip saw himself as the defender of Catholic Europe against the Ottoman Empire and the Protestant Reformation, and invested Spain's position as the leading European power in multiple simultaneous warring efforts.

This is a list of Portuguese monarchs who ruled from the establishment of the Kingdom of Portugal, in 1139, to the deposition of the Portuguese monarchy and creation of the Portuguese Republic with the 5 October 1910 revolution.

Through the nearly 800 years in which Portugal was a monarchy, the kings held various other titles and pretensions. Two kings of Portugal, Ferdinand I and Afonso V, claimed the crown of Castile and waged wars in order to enforce their respective claims. Ferdinand I managed to be recognized as King of Galiza in 1369, although his dominance of the region was short-lived. When the House of Habsburg came into power, the kings of Spain, Naples, and Sicily also became kings of Portugal. The House of Braganza brought numerous titles to the Portuguese Crown – some honorary, such as the attribution of the title of Rex Fidelissimus (His Most Faithful Majesty), and royal titles, such as King of Brazil and then de jure Emperor of Brazil.

Roger I (Italian: Ruggero; Arabic: رُجار, romanized: Rujār; Maltese: Ruġġieru; Norse: Rogeirr; c. 1031 – 22 June 1101), nicknamed "Roger Bosso" and "Grand Count Roger", was a Norman nobleman who became the first Grand Count of Sicily from 1071 to 1101.

As a member of the House of Hauteville, he participated in several military expeditions against the Emirate of Sicily (beginning in 1061). He was later invested with part of Sicily by his brother, Robert Guiscard, Duke of Apulia, in 1071. By 1090, he had conquered the entire island. In 1091, he conquered Malta. The state he created was merged with the Duchy of Apulia in 1127 and became the Kingdom of Sicily in 1130. His descendants in the male line continued to rule Sicily down to 1194.

Philip III (Spanish: Felipe III, Portuguese: Filipe II; 14 April 1578 – 31 March 1621) was King of Spain and Portugal (as Philip II) during the period known as the Iberian Union, reigning from 1598 until his death in 1621. He was also King of Naples and Sicily, Duke of Milan, and Lord of the Seventeen Provinces. A member of the House of Habsburg, he was born in Madrid to King Philip II of Spain and his fourth wife, Anna of Austria. The family was heavily inbred; Philip II and Anna were uncle and niece, as well as cousins.

One year after inheriting the throne, he married his Habsburg cousin Margaret of Austria, the sister of Ferdinand II, Holy Roman Emperor. Philip quickly delegated most of his power and duties to his chief minister, the Duke of Lerma, whose influence shaped much of his reign. In the outskirts of his territories, military power was upheld by successful but capricious proconsuls, such as Ambrogio Spinola and the Duke of Osuna. Though Philip is associated with a period of relative peace in Western Europe, called the Pax Hispanica by some historians, his lack of focus contributed to the Spanish Empire's gradual decline.