Spanish La Liga and Copa del Rey winners

I'm a dictator, do as I tell you

After the Spanish Civil War (1936-39) Franco banned the use of non-Spanish language and names, in much the same way as Mussolini did with Internazionale in Italy. This led to a number of clubs having to change their names to conform.
With the exception of Atlético Madrid, they all changed their names back after Franco died. To save confusion I've kept to their present names throughout, but added some detail below.

•  1: Club Vizcaya became Athletic Bilbao in 1903.
•  2: Club Ciclista San Sebastian became Real Sociedad in 1909.
•  3: In 1910 and 1913 the clubs briefly split into two rival federations the Copa UECF and the Copa FEF, hence the two winners for those years.
•  4: Madrid became Real Madrid in 1920.
•  5: Racing Club Irún, who won the Copa FEF in 1913, became Real Unión in 1915.
•  6: RCD Espanyol have changed their name on numerous occassions. They started life as Sociedad Española de Football in 1900. In 1912 they were granted the royal "Real" to become Real Club Deportivo Español (RCD Español). At the declaration of the Second Spanish Republic in 1931 they changed to Club Esportiu Espanyol (CE Espanyol) and after the Spanish Civil War (1939) back to RCD Español. Finally in 1995 they changed to the more Catalan (almost) name of Reial Club Deportiu Espanyol.
•  7: Atlético Madrid were formed in 1903 by Basque students living in Madrid, hence their original name of Athletic Club de Madrid. By the time the Spanish Civil War had ended they had merged with Aviación Nacional from Zaragoza, to become Atlético Aviación. In 1947 the club dropped the air force association from its name and became Atlético Madrid.
•  8: After the Spanish Civil War, the Catalan language and flag were banned, the use of non-Spanish names was also prohibited. These measures led to FC Barcelona having its name forcibly changed to Club de Fútbol Barcelona and the removal of the Catalan flag from the club shield. The club changed its official name back to Futbol Club Barcelona in 1974.
•  9: In 1980 Castilla CF were well beaten by Real Madrid 6-1. Castilla CF were in fact Real Madrid's reserve team, who had beaten four La Liga teams on the way to the final. They have been known as Real Madrid B since 1991.

Research

I've cross referenced as much as possible and added links to the new club website where possible. Many thanks goes to the RSSSF Archive, which was an invaluable source of information whenever an insolvable fact was needed. If you need to find a football answer, it will be on there somewhere.