I too remember seeing Louis Armstrong at the Empress Hall, Earls Court. This was the first time an American jazz band had come to the UK after years of being banned by the American Federation of Musicians, so it was a really special event. HOWEVER, the promoters obviously didn't realise how popular Satch would be - as they filled out the programme with a large lady singer, Velma Myddleton and a one-legged tap dancer! That was Peg-leg Bates, who I believe died only recently. Louis and the All-stars performed on a stage that revolved throughout the show... memories!
Armstrong practically invented modern vocal styling - before him there was nothing so relaxed and inventive - Bing Crosby was the first white performer to pick up on it. His classic early recordings are still able to amaze us, numbers like West End Blues - pure magic.