What do you mean? First off, everything about the Revolution in the game is wrong, simplifying it down to two factions is silly. Take a look at this article:
http://en.wikipedia.org/wiki/List_of_factions_in_the_Mexican_Revolution
So, the faction we know as Revolutionary Mexico should be known as the Constitutionalistas, and Mexico should be in control of Victoriano Huerta (Authoritarian Democrat). Later in 1914, the Constitutionalists defeat Mexico, at which point their leaders split off: the Carranzistas control the government (Social Conservative), the Division del Norte under Pancho Villa controls the north (IDK, something like Radical Socialist), and the Zapatistas under Emiliano Zapata (also Radical Socialist I guess) control the south. In 1919, the Zapatista movement collapses after the government assasinates Zapata. In 1920, the government signs a treaty with Villa, and he lays down arms.