Victory Conditions are a fine art in historical games. For the side that won the conflict, you generally want conditions that mirror the historical result. For the side that was defeated, you'll either need to come up with a reasonable hypothetical of what victory would have looked like, or, in cases that are really lopsided, you'll need to resort to "lose the battle, but win in game terms" conditions - the side still loses, but loses in a less humiliating and decisive fashion, which is enough to give the disadvantaged player a fair shot at winning the game.
What happens, however, when neither side "loses" during the conflict or period being simulated? How does a side "win" when neither side wins? That was the question I grappled with when I started putting together This Guilty Land. That game takes as its subject the political struggle over slavery in the decades leading up to the American Civil War, with one side, Justice, pursuing the abolition of slavery, and the other, Oppression, agitating for its preservation and even expansion.
The game doesn't simulate the war itself. The game also assumes that the war would have been resolved in roughly the same way it was historically, with a Union military victory and the emancipation of African-Americans. If Justice wins the game, the war begins, the South loses, and the slaves are freed. If Oppression wins the game, the war begins, the South loses, and the slaves are freed. In this sense, the players have no impact on the end result of the conflict, and in a way, that's the point. The Civil War was not the result of some failure to compromise, something that could or should have been avoided, as some have proposed. Compromise on that subject was and is abhorrent: neither side would or could ever have convinced the other. It is difficult to condemn "extremism" and intransigence when one side was clearly right and the other wrong. This is a conflict that never could have been resolved legislatively or through debate. The thesis of the game, then, is that the Civil War was not only inevitable but necessary, and that the question of American slavery could only be resolved by warfare.
So the first question this raises is, how does one come up with victory conditions when, during the period being simulated, neither side had achieved their aims? Partially this was resolved by assigning Victory Points to various accomplishments: the player with the most VP at the end of the game wins. Cumulative VP are scored every turn for shifting Laws onto one's side, and both players can "buy" VP by expending excess Political Will. Forming political parties will score VP, but this will radicalize some of your supporters while driving the others toward squishy, insidious centrism.
But because of certain systemic factors - factors that are crucial to understanding the period and the game - Oppression was coming up with far more VP than Justice. Briefly I toyed with Justice having a non-VP victory condition, but that lacked tension, and saw Justice dedicate their efforts solely to that Victory Condition, ignoring what Oppression was doing. In a game about deadlock, having both players treating it like a "multiplayer solitaire" eurogame is not acceptable. So instead, I turned Justice's non-VP-scoring Victory Condition into something that scored game end VP - 1 VP per Support. Unless they really steamroller over Oppression in that regard, they'll need to score some VP in other ways, and deny Oppression VP opportunities, if they want to come out on top. As a result, so far in testing the game is very close when the players are close, but can be a blow-out when one player is clearly dominating the proceedings. If you've read some of these articles before, then you know that's pretty much where I want it, balance-wise.
The second question raised by this situation is, why would you simulate this at all? Why simulate a conflict - the legislative battle over slavery - that can, by my own metric, never have a winner? I think the answer is actually embedded in the question. I think it's important to understand why the issue could not, and could never, have been resolved peacefully or through the "normal" channels of civil debate and legislation. In fact, those "normal" channels only served to entrench and perpetuate the rot at the center of our republic.