On 16 March 1938, Barcelona came under aerial bombardment from the Italian Air Force, causing more than 3,000 deaths, with one of the bombs hitting the club's offices. A few months later, Catalonia came under occupation and as a symbol of the "undisciplined" <answer>Catalan</answer>ism, the club, now down to just 3,486 members, faced a number of restrictions. All signs of regional nationalism, including language, flag and other signs of separatism were banned throughout Spain. The <answer>Catalan</answer> flag was banned and the club were prohibited from using non-Spanish names. These measures forced the club to change its name to Club de Fútbol Barcelona and to remove the <answer>Catalan</answer> flag from its crest.
What flag was removed from the club's crest?
Catalan