This is one of the most fun strategy games for HIstory fans ever made. It is a three-way war between the Kievan Rus (Russia), the Golden Horde (Mongols), and the Teutonic Order (Crusaders). You get some historical heroes in each mission, but what makes this game really stand out is the RPG mechanics. This isn't a game where you plop down a base and start pouring Elite Knights out of the barracks. You begin with some actual elite warriors, but that is all you get, you must supplement them with peasants. However, each unit levels up with battle experience and you can equip them with whatever gear you want, and the more they use that weapon/fighting style the more they become like those original elite units. EX. Take a peasant, give him armor, a shield, and a mace, and if he should stay alive through the different battles, he will eventually level up to be as strong as a hero unit. I In most strategy games you have "swordsmen, archers, calvary" and that is their roll.
In this you can give an archer a lance and shield and stick them on a horse, and you now have a calvary unit. You can then take off the lance, give them a sword and they are now a swordsman. It isn't smart to do this because, as stated, units gain strength from doing, so you do want units more focused, but it can be done.
It is really cool how much of a mishmash of forces you can band together. Having warriors with 2-handed warhammers mixed in with spearmen, crossbowmen, swordsmen-archer hybrids, mounted knights, a few horse archers, building your army really does feel like forming an D&D style party. I do wish there was a system with perks and abilities to add; however, the game is still a ton of fun by itself.
Note: There is a game on Steam that used the Golden Horde as a template called Ancient Wars: Medieval Crusades. I own it, and while it is a well-made game with a lot of heart, a lot of the systems were changed (streamlined equipment management), which hurt the overall experience.