Lithuania
Eastern Europe includes the countries of Belarus, Estonia, Latvia, Lithuania, Poland, the European part of Russia and Ukraine. All these countries share important parts of their history, for example Poland and the Baltic States, Poland and Ukraine, and Russia and Ukraine. This also means that they share a number of their heroes, immortalized by building them an equestrian statue.
I found most of the equestrian statues in Russia (34), Ukraine (13) and Poland (12). Some of these statues have an interesting history. I also found one statue in each of the Baltic countries, but none in Belarus.