In Catalonia the War of the Spanish Succession ended on 11 September 1714 and signalled the start of an era when various rights and liberties were lost. Catalan National Day marks the defeat on 11 September, which is all about actively standing up to oppression.
The date was chosen as the national day for its symbolism and throughout the day Barcelona and other cities around Catalonia speak out via organised acts, as well as arranging recreational activities, concerts, award ceremonies and speeches.
http://agenda500.barcelona.cat/en/detall/catalan-national-day_99400458329.html
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