Anthracite
Thank you Anthracite! 
The Bulgarian leaders before WW1 were called tsars. This title was earned in 705 CE, in return for putting Emperor Justinian back on the throne.
John Julius Norwich’s A Short History of Byzantium p. 105
-curtis
Really? I can only name Germany and Russia…what else was there? (and, for historical note, Czar and Tsar are the same thing)
** 2sense **
Really? I can only name Germany and Russia…what else was there? So, you named Bulgaria…but Austria was ruled by the Hapsburg for as long as it was independent (I think, I’m not so sure about this…) (and, for historical note, Czar and Tsar are the same thing)
**Glitch
Up until that point, your logic basically made sense. The Mongols are in many ways like the Israeli’s (in this case)- they could defeat their enemies in battle, but couldn’t conquer them. The analogy dies there- Israeli’s because they lacked the numbers to occupy, Mondolians because of the terrain. The Russian steppe, the Fertile Crescent, and Northern China, are all wide open spaces. Western Europe is not. As I said in my original post, it depends on the terrain. I suppose that if Rome were foolish enough to commit most of its forces to a battle outside their natural defenses, they would lose, but otherwise the mongols would not fare so well.
If a handful of barbarian nations could destroy Rome, then it must be possible for a huge horde like the Kahn’s to do it, right? In the same circumstance, of course, but we’re talking about the hey day of the Roman empire, that platuea that jti mentioned, when everyone was happy, content, and efficient, though not so ambitious…Anyway, right then, Rome was as untouchable as England in 1930 (though, of course, for different reasons.) It was beyond Mongolia’s power to infiltrate through western Europe, and then use tactics like those of the barbarians. Again, the terrain prevents their success.