Land locked countries, rarely have an effective navy. And their ponies could not swim that far.
Historically, the Mongolian Navy was one of the largest in the world, during the time of Kublai Khan (Grandson of GK). However, most of the fleet sank in a Typhoon during the Mongol invasions of Japan. Which may explain your theory on the inability of ponies to swim

. Austria had a Med Fleet 1st WW. In fact interestingly Azerbaijan operates a Fleet on the Caspian Sea,