Well actually, there are THREE Campaigns:
The third, Revelation is the hidden story that is unlockable DLC after you clear Birthright or Conquest. See Serenes Forest for full deails on the game but as indicated, this is the first non-Pokemon Nintendo game that comes in multiple flavors. Given the Fire Emblem franchise was riding on the (financial) success of Awakening, it’s safe to say Fire Emblem will be around for a while longer. The catch is it will likely be handheld only: The original plan was for Awakening (when it was in its early stages) to be released as a console game but Nintendo didn’t feel the profit was worth the investment so it was released on the 3DS instead.
…Fates is likely Nintendo’s way of ensuring Awakening’s success wasn’t a fluke: I’ve played all the Fire Emblem games released in the U.S. as well as Binding Blade (with a fan translation). Fans love their Fire Emblem but sales for 8 through 10–especially in the U.S.–were atrocious. I find this interesting given I still own ALL the Fire Emblem games released in the U.S. Alas, at least the U.S. got the next Fire Emblem: FE 1 through 6 were Japan-only releases and the DS Fire Emblem game before Awakening was only released in Japan.
All that said, here’s the basic premise. You are Corrin, a Prince/Princess of born in Hoshido but raised in Nohr. Hoshido (Birthright), a peace-loving nation is in conflict with Nohr (Conquest), a glory-seeking nation. As a Prince/Princess in the unique position of claiming both nations as their homeland, at a certain point early in the game you will be forced to choose: The nation of your birth or the nation that raised you.
Such is the story of Conquest and Birthright. In the retail versions, you are locked into one or the other but you can buy the other campaign for half the price from the eShop. Those who buy the digital version will get to choose one or the other. Once they’ve chosen, they will need to pay to unlock the rest of the campaign they picked. Plus you can buy the other choice from the eShop with the same discount of course.
Now, the obvious next question should be is “Why are both Campaigns made into separate games and not like Sacred Stones with both rolled into one game?” The answer: Each campaign alone is as long as Awakening. That’s the first reason. The second reason is each campaign offers a vastly different experience from the characters to the weapon names to where you will be. In Sacred Stones, even though Eirika and Ephraim split up for about half the game, you still saw all the same recruitable characters regardless of which royal you finished the game with. The storyline doesn’t really change much and you had access to the maps the other royal traveled through after Chapter 16.
With Conquest and Birthright, you are locked completely out of the other campaign after you’ve made your choice. Free of charge, anyway. Also unlike both Awakening AND Sacred Stones, the player character is also the games’ main Lord. Eirika and Ephraim were the Lords in Sacred Stones but they prettymuch traversed the same world. Chrom was the main Lord in Awakening and was joined by Robin, who is a Tactician. Speaking of Corrin, it was revealed last month Corrin will br the final playable character in Super Smash Bros. 3DS/Wii U. Hence the above picture. Corrin’s inclusion being cross-game advertisement ala Robin and Lucina for Awakening, this us hopefully a sign from Nintendo that Fire Emblem will be around for years to come.
Speaking of Sacred Stones:
…I’d say it’s about time for a remake ala Fates.