Kingdom of the Two Sicilies in the context of "House of Bourbon-Two Sicilies"

A constitution, or supreme law, is the aggregate of fundamental principles or established precedents that constitute the legal basis of a polity, organization or other type of entity, and commonly determines how that entity is to be governed.

When these principles are written down into a single document or set of legal documents, those documents may be said to embody a written constitution; if they are encompassed in a single comprehensive document, it is said to embody a codified constitution. The constitution of the United Kingdom is a notable example of an uncodified constitution; it is instead written in numerous fundamental acts of a legislature, court cases, and treaties.

Southern Italy, also known as Meridione ([meriˈdjoːne]) or Mezzogiorno ([ˌmɛddzoˈdʒorno] ), is a macroregion of Italy consisting of its southern regions.

The term "Mezzogiorno" today mostly refers to the regions that are associated with the people, lands or culture of the historical and cultural region that was once politically under the administration of the former Kingdoms of Naples and Sicily (officially denominated as one entity Regnum Siciliae citra Pharum and ultra Pharum, i.e. "Kingdom of Sicily on the other side of the Strait" and "across the Strait") and which later shared a common organization into Italy's largest pre-unitarian state, the Kingdom of the Two Sicilies.

Apulia (/əˈpuːliə/ ə-POO-lee-ə), also known by its Italian name Puglia (Italian: [ˈpuʎʎa]), is a region of Italy, located in the southern peninsular section of the country, bordering the Adriatic Sea to the east, the Strait of Otranto and Ionian Sea to the southeast and the Gulf of Taranto to the south. The region comprises 19,345 square kilometers (7,469 sq mi), and has 3,874,166 inhabitants as of 2025. It is bordered by the other Italian regions of Molise to the north, Campania to the west, and Basilicata to the southwest. The regional capital is Bari.

In ancient times, more precisely at the beginning of the first millennium BC, the region of Apulia was inhabited by the Iapygians, while during the 8th century BC its coastal areas were populated by ancient Greeks. Later, the region was conquered by the ancient Romans. It was then conquered by the Byzantines, followed by the Normans, the Aragonese and the Spanish. Subsequently, it became part of the Kingdom of the Two Sicilies, to then be annexed to the unified Kingdom of Italy after the Expedition of the Thousand.

The Kingdom of Sicily (Latin: Regnum Siciliae; Sicilian: Regnu di Sicilia; Italian: Regno di Sicilia) was a state that existed in Sicily and the southern Italian Peninsula as well as, for a time, in Northern Africa, from its founding by Roger II of Sicily in 1130 until 1816. It was a successor state of the County of Sicily, which had been founded in 1071 during the Norman conquest of the southern peninsula. The island was divided into three regions: Val di Mazara, Val Demone and Val di Noto.

After a brief rule by Charles of Anjou, a revolt in 1282 known as the Sicilian Vespers threw off Angevin rule in the island of Sicily. The Angevins managed to maintain control in the mainland part of the kingdom, which became a separate entity also styled Kingdom of Sicily, although it is retroactively referred to as the Kingdom of Naples. The Kingdom of Sicily on the island(also known as Kingdom of Trinacria between 1282 and 1442) on the other hand, remained an independent kingdom ruled by relatives of the House of Barcelona, and was then added permanently to the Crown of Aragon as a result of the Compromise of Caspe of 1412. Following the dynastic union of the crowns of Castile and Aragon in 1479, it was a viceroyalty of the Spanish kingdom. During the War of the Spanish Succession (1700–1714), the island was taken over by the House of Savoy. In 1720, Savoy gave it to Austria in exchange for Sardinia. Later, the island was ruled by a branch of the Bourbons. Following the Napoleonic period, the Kingdom of Sicily was formally merged with the Kingdom of Naples to form the Kingdom of the Two Sicilies, which in 1861 became part of the new unified Kingdom of Italy.

The House of Bonaparte (originally Buonaparte) is a former imperial and royal European dynasty of French and Italian origin. It was founded in 1804 by Napoleon I, the son of Corsican nobleman Carlo Buonaparte and Letizia Buonaparte (née Ramolino). Napoleon was a French military leader who rose to power during the French Revolution and who, in 1804, transformed the French First Republic into the First French Empire, five years after his coup d'état of November 1799 (18 Brumaire). Napoleon and the Grande Armée had to fight against every major European power (except for the ones he was allied with, including Denmark-Norway) and dominated continental Europe through a series of military victories during the Napoleonic Wars. He installed members of his family on the thrones of client states, expanding the power of the dynasty.

The House of Bonaparte formed the Imperial House of France during the French Empire, together with some non-Bonaparte family members. In addition to holding the title of Emperor of the French, the Bonaparte dynasty held various other titles and territories during the Napoleonic Wars, including the Kingdom of Italy, the Kingdom of the Spain and the Indies, the Kingdom of Westphalia, the Kingdom of Holland, and the Kingdom of Naples. The dynasty held power for around a decade until the Napoleonic Wars began to take their toll. Making very powerful enemies, such as Austria, Britain, Russia, and Prussia, as well as royalist (particularly Bourbon) restorational movements in France, Spain, the Two Sicilies, and Sardinia, the dynasty eventually collapsed due to the final defeat of Napoleon I at the Battle of Waterloo and the restoration of the Bourbon dynasty by the Congress of Vienna.

The Kingdom of Naples, officially the Kingdom of Sicily, was a state that ruled the part of the Italian Peninsula south of the Papal States between 1282 and 1816. It was established by the War of the Sicilian Vespers (1282–1302). Until then, the island of Sicily and southern Italy had constituted the "Kingdom of Sicily". When the island of Sicily revolted and was conquered by the Crown of Aragon, it become a separate kingdom also called the Kingdom of Sicily. This left the Neapolitan mainland in the possession of Charles of Anjou who continued to use the name "Kingdom of Sicily". Later, two competing lines of the Angevin family competed for the Kingdom of Naples in the late 14th century, which resulted in the murder of Joanna I at the hands of her successor, Charles III of Naples. Charles' daughter Joanna II adopted King Alfonso V of Aragon as heir, who would then unite Naples into his Aragonese dominions in 1442.

As part of the Italian Wars, France briefly ruled the territory in 1494 and at the beginning of the 16th century; it then went to war with Spain over the kingdom in 1502, a conflict that ended in a victory for Ferdinand II, who was in full control of the kingdom by 1504. The Spanish held control of Naples throughout the 17th century where it remained an important source of economic and military power for the Spanish Crown. After the War of the Spanish Succession in the early 18th century, the possession of the kingdom again changed hands; the 1714 Treaty of Rastatt saw Naples given to Charles VI of the Austrian Habsburgs. However, Naples and Sicily were conquered by Charles, Duke of Parma (of the Spanish Bourbons) during the War of the Polish Succession in 1734, he was then installed as King of Naples and Sicily from 1735. In 1816, Naples formally unified with the island of Sicily to form the Kingdom of the Two Sicilies.

The Expedition of the Thousand (Italian: Spedizione dei Mille) was an event of the unification of Italy that took place in 1860. A corps of volunteers led by Giuseppe Garibaldi sailed from Quarto al Mare near Genoa and landed in Marsala, Sicily, in order to conquer the Kingdom of the Two Sicilies, ruled by the Spanish House of Bourbon-Two Sicilies. The name of the expedition derives from the initial number of participants, which was around 1,000 people.

The Garibaldians, with the contribution of southern volunteers and reinforcements to the expedition, increased in number, creating the Southern Army. After a campaign of a few months with some victorious battles against the Bourbon army, the Thousand and the newborn southern army managed to conquer the entire Kingdom of the Two Sicilies. The expedition was a success and concluded with a plebiscite that brought Naples and Sicily into the Kingdom of Piedmont-Sardinia, the last territorial conquest before the proclamation of the Kingdom of Italy on 17 March 1861. The Expedition of the Thousand was the only desired action that was jointly decided by the four "Fathers of the Fatherland": Giuseppe Mazzini, Giuseppe Garibaldi, King Victor Emmanuel II, and Camillo Benso, Count of Cavour, pursuing divergent goals. Mazzini, of republican political belief, wanted to liberate Southern Italy and Rome, while Garibaldi wanted to conquer, in the name of Victor Emmanuel II, the Kingdom of the Two Sicilies and continue towards Rome to complete the Italian unification, while Cavour wanted to prevent the conquest of Rome to avoid a conflict with his French ally, Napoleon III, who protected the Papal States.