Liber maiolichinus de gestis Pisanorum illustribus in the context of "Formentera"

The Principality of Catalonia was a medieval and early modern state in the northeastern Iberian Peninsula. During most of its history it was in dynastic union with the Kingdom of Aragon, constituting together the Crown of Aragon. Between the 13th and the 18th centuries, it was bordered by the Kingdom of Aragon to the west, the Kingdom of Valencia to the south, the Kingdom of France to the north and by the Mediterranean Sea to the east. Its sovereign or prince had the title of Count of Barcelona. The term Principality of Catalonia was official until the 1830s, when the Spanish government implemented the centralized provincial division, but remained in popular and informal contexts. Today, the term Principat ("Principality") is used primarily to refer to the autonomous community of Catalonia in Spain, as distinct from the other Catalan Countries, and often including the historical region of Roussillon in Southern France.

The first reference to Catalonia and the Catalans appears in the Liber maiolichinus de gestis Pisanorum illustribus, a Pisan chronicle (written between 1117 and 1125) of the conquest of Majorca by a joint force of Northern Italians, Catalans, and Occitans. At the time, Catalonia did not yet exist as a political entity, though the use of this term seems to acknowledge Catalonia as a cultural or geographical entity. The counties that eventually made up the Principality of Catalonia were gradually unified under the rule of the count of Barcelona. In 1137, the County of Barcelona and the Kingdom of Aragon were unified under a single dynasty, creating what modern historians call the Crown of Aragon; however, Aragon and Catalonia retained their own political structure and legal systems, developing separate political communities along the next centuries. Under Alfons I the Troubador (1164–1196), Catalonia was regarded as a legal entity for the first time in 1173. Still, the term Principality of Catalonia was not used legally until the 14th century, when it was applied to the territories ruled by the Courts of Catalonia.