Polo is a popular sport in Argentina and many of the best players in the world come from there.
Horses and breeding for polo have a long history in Argentina, and probably like Australia, there is land space and an established rural farming industry which lends itself to horses and horsemanship.
There are a number of famous polo families in Argentina and is certainly easier, and sometimes the only way, to develop a high level professional career. This is due to the need for established breeding lines and money for such a sport.
There are three major open tournaments in Argentina which are amongst the best in the world; Hurlingham, Tortugas, and the Argentine open.