I think this is an important question.
1. Can any factions, dynamics, tendencies, individuals be thought of as "protagonists" from an EA perspective?
2. Could you make this determination in real time?
3. What factions, dynamics, tendencies, individuals were missing?
Feel free to assume that you'd start from some privilege (can read and write, mostly), if you want to factor out a heroic rags to riches prologue.
My first guess, based on the knowledge I have, is that the abolitionist faction was good, and that supporting them would be necessary for an EA in that time (but maybe not sufficient). Additionally, my guess is that I'd be able to determine this in real time.