NFL had a brief period of relative popularity in England for a few years, when Channel 4 started broadcasting NFL games in the late eighties (I think).
After a while, interest fell away, ratings fell, and they dropped the coverage.
Here in Europe, football, as we call it, or soccer, is king. Personally I can rarely abide it. There's Field Hockey, which is quite popular. A bit more popular is Rugby, which is actually two games: Ruby Union, the sport of kings IMHO, and Rugby Leauge, which is a bastard offspring of true rugby, and which has a closer similarity to American Football than true rugby. Both games involve carrying the ball. The ball is never thrown forward, only backwards. As with American Football, the ball can be carried over the end line for lots of points, and then kicked through posts for very few. Kicks over the posts get more points in the run of play. To say that both sports are physical is an understatement. There is one team for all possible plays, and play is virtually continuous over two halves. No padding is worn.
Compared to American Football, Rugby Union is a fluid, dynamic game with rapid changes, and non-stop action. The rules about passing the ball back mean that plays are ripples of men up the pitch, running forward and passing back. Quite easy if it were not for the fact the other team want to pull you to the ground. One unique feature of Rugby is the scrum. AT certain points when the ball is dead, the two opposing teams form semi-circles (think one half of group hug, all weighing 200-250lbs, with the dispositon of a bear with tooth-ache). The two halves are lined up and charge each other, ending up in push of war. Into this circle of men the ball is injected, and the players in the scrum take time off from eating their opponent's ear to hack and stab with their boots in an attempt to kick the ball back to an unfortunate individual who has to pull the ball out of the mess.
It is a fun sport.
There's couple of Irish games there are other people far more qualified to comment on, and people who know more about Australian Rules, which seems to me to be a cross between head-butting, basketball, and rugby.
