That's a big question! What you're looking for is army and unit management and generally games that are all about that are considered strategy games, not RPGs. Let's see what I can do.
Dragon Force for the Sega Saturn is a strategy game with heavy RPG elements where you control one of several forces on a map and try to conquer the world. There are lots of story events that happen as you play and they can change depending on how you deal with enemies and who you're playing as. Your characters all participate in the story and often have little side stories of their own.
Brigandine (I can't find any videos without some guy mumbling over footage, sorry!) for the Playstation is pretty similar to Dragon Force; you play as one of several countries on a map with the goal of conquering all the other countries. There's a story that pans out, your characters are mostly unique, participate in the story and the story can change depending on how you conquer the world.
In
King of Dragon Pass for the PC, you control a bronze age clan that just immigrated into a mythical valley full of crazy magic creatures and rival clans. You play as the clan ring and control your clan's warfare, diplomacy, exploration, agriculture and trade. The most fun thing about the game, though, is the event system. Every season, you'll get several events that require the arbitration of the ring. A lot of the time, these events can have long-lasting effects and you have to think carefully how you handle them. This is a very fun and charming game and if you like Mount and Blade, I think you'll enjoy this too. An updated version came out exclusively for the iPad and iPhone so you might want to check that out if you've got one.
In
Romancing SaGa 2 for the SNES, you control the emperor or empress of Avalon over multiple generations as you expand your kingdom. It's non-linear, you can do things and explore in whatever order you'd like. You can upgrade your castle, control troops and expand into neighboring regions. A lot of the time it plays like a JRPG so maybe this is what you're looking for.
Romance of the Three Kingdoms X is a Playstation 2 game (there's also a poorly translated PC version that's hard to get running and not really worth it!) you play as one of several hundred characters during the fall of the Han Dynasty in ancient China. The game is completely open ended and non-linear, you can wander around ancient China challenging guys to duels or join a warlord's army as a subordinate officer or start your own and conquer the country. Mechanically it's not very similar to Mount and Blade, but it's got a lot of similar concepts - vassalage, declaring independence and forming your own country, wandering around a big world that changes whether or not you're participating in it. You might like it!
It's hard to find good videos!!!
Jagged Alliance 2 is a PC strategy RPG where you control a small unit of mercenaries that's been hired to kill the dictator of a country. Along the way, you take over villages and mines to accrue resources you need to hire more mercenaries and train militia troops to defend the villages. It's a very complex game with deep strategical combat, much more than Mount and Blade but the roleplaying elements, character stats, talking to villagers, leveling up, are a lot of fun. All of the mercenaries have their own personalities and some are pretty funny.
Sid Meier's Pirates for the PC is a completely open world pirate simulator where you sail around the Caribbean raiding other ships or working as a corsair for one of four countries. You can conquer towns or hunt down other pirates or search for treasure or fight in wars as a privateer; there's a lot you can do and it's very similar to Mount and Blade, except that you can't declare independence.
Hopefully you'll like one of these! I can think of some others, but these are the ones I think you'll like the most.
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