The Count of Barcelona was a title held by the rulers of the County of Barcelona, a historical region in present-day Catalonia, Spain. This title emerged in the early Middle Ages and was significant in the formation of the Crown of Aragon. The counts played a crucial role in the political and military affairs of the region, often engaging in alliances and conflicts with neighboring territories. The title of Count of Barcelona was held by various noble families, most notably the House of Barcelona. In 1137, the title was united with the Crown of Aragon when Ramón Berenguer IV married Petronila of Aragon, marking a pivotal moment in the history of the region. The countship eventually became part of the broader Spanish monarchy.