Water polo was contested at the 1900 Olympics and a water polo tournament was again held in 1904 at St. Louis. However, the sport was somewhat different as it used the American variant of the sport in 1904, which used a very soft ball and was noted to be much rougher and more brutal.
Three American club teams competed. A German team tried to enter but its entry was refused because the players did not all play for the same club. One could easily make the argument that this should disqualify the sport for Olympic consideration in 1904.
The event was held at the Life Saving Exhibition Lake which was an artificial lake constructed for the agricultural exhibits of the Louisiana Purchase Exposition. Swimming and diving were also held in this lake, but on the other end of the lake, cattle from the agricultural exhibits often grazed and cooled themselves off in the lake. Within one year of the Olympic water polo event, four of the players died from typhus, although in that era, when typhus was rampant, it is difficult to be certain that these two facts were fully associated.
USA