In 1137, Ramon Berenguer IV, Count of Barcelona accepted King Ramiro II of Aragon's proposal to marry Queen Petronila, establishing the dynastic union of the County of Barcelona with the Kingdom of Aragon, creating the Crown of Aragon, while the County of Barcelona and the other Catalan counties adopted a common polity known as Principality of Catalonia, which developed an institutional system (Courts, constitutions, Generalitat) that limited the power of the kings. Catalonia contributed to the expansion of the Crown's trade and military, most significantly their navy. The Catalan language flourished and expanded as more territories were added to the Crown of Aragon, including Valencia, the Balearic Islands, Sardinia, Sicily, Naples, and Athens. The crisis of the 14th century, the end of the reign of House of Barcelona and a civil war (1462–1472) weakened the role of the Principality in Crown and international affairs.