Judging by recent performances, Barcelona. But, Real Madrid has won more La Liga's and more Champions League titles. In England, Manchester United are the most successful at the moment, but Liverpool have the second most Premier League titles. Only a one behind Man U. Liverpool also have more Champions League titles than Man U and Barcelona.
Out of Real Madrid and Liverpool I'd say Real Madrid, but I'm a huge Liverpool fan!
The Arkansas Razorbacks from the University of Arkansas are the most successful Arkansas football team. Arkansas does not have a National Football team, therefore the most successful team would be a college team.
It is arsenal .F.C.
Rangers Football Club are the most domestically successful football team in the world
New England Patroits
obviously Manchester united. Even though i am not a united fan, they rule the whole of England and most of Europe. Manchester Utd are not the most successful but they are possibly the best football team in the world. Glasgow Rangers are the most successful domestic team in the world with winning the Scottish Premier League 52 teams which is a world record and also winning 110 trophies altogether.
I think Liverpool FC
Glasgow Rangers Football Club