Polo can be played on a horse of any height 

As the game originate in the foothills of Manipur , it was played on ponies. Same restrictions were observed  when Mughals and Britishers first started playing polo.In 1895 max height was raise from 14 to 14.2 hands. Post World War 1 , due to acute shortage of horses of require height , the restriction was remove completely in the year 1919.