Ramon Berenguer IV, sometimes called the Saint, was the count of Barcelona and the consort of Aragon who brought about the union of the County of Barcelona with the Kingdom of Aragon to form the Crown of Aragon.

The count of Barcelona was the ruler of the County of Barcelona and also, by extension and according with the Usages and Catalan constitutions, of the Principality of Catalonia as Princeps for much of Catalan history, from the 9th century until the 18th century. After 1164, with Alfonso II of Aragon and I of Barcelona, the title of count of Barcelona was united with that of king of Aragon, and after the 16th century, with that of king of Spain.