The term 'Palindromic Band of Swedes' refers to the Swedish pop group ABBA, which is a four-letter palindrome. ABBA was one of the most successful music groups of all time, having sold over 380 million records worldwide. They were formed in Stockholm in 1972 and achieved international success with their catchy pop songs and iconic costumes. The band split up in 1982, but their music continues to be popular today.