From the mid-13th century on, no more charters were granted, as the demographic pressure had disappeared and other means of re-population were created. "Fueros" remained as city charters until the 18th century in Aragon, Valencia and Catalonia and until the 19th century in Castile and Navarre. "Fueros" had an immense importance for those living under them, who were prepared to go to war to defend their rights under the charter. In the 19th century, the abolition of the "fueros" in Navarre would be one of the causes of the Carlist Wars. In Castile, disputes over the system contributed to the war against Charles I (Castilian War of the Communities).