History of Spain between 1939-1950?
During this time, Spain was in the European union and prospering WRONG! The EU didn't exist at that time. In fact, its predecessor organization, the EEC, wasn't even founded until 1957 and did not include Spain. Until 1975 Spain was in the grip of a fascist dictatorship run by Generalissimo Francisco Franco. Conditions were anything but prosperous. This is far too broad a question to be answered here in any greater detail. Please see any decent book about 20th century European history.