There's been quite a few leagues in Britain, unfortunately sometimes at the same time. The USAF had its own league for a long time, even played their finals at Wembley. The first game I saw was an exhibtion match during the Edinburgh Festival - (Chicksands) Fighting Chicks v the Suffolk Titans on 1 September 1962 at Goldenacre, then the Chicks were back a year later at Inverleith facing the Sabres from France. I supported the Ravens because they were the first British team I saw that played as if they knew what they were doing Victor Ebubedike (later Mohammed) ended up on the NY Jets squad.