Hablen español, already | The Economist

Also unmentioned is one of the reasons relatively few people master the minority languages: Francisco Franco’s una bandera, una patria, una lengua policies, which forbade everything from Catalan names to shop-signs in Basque. These gave the minority regions enduring grievances, grievances which are inflamed when Castilian-speakers (and outsiders) treat them as pests for wanting to speak their own languages in their own country.