All history in fact is a clear line, regardless of our ability to see it. Our future appears as a cone of probablilty bounded by physical and human limitations but as the moment passes this too, becomes part of the sharp edge of factual history. For most the light that guides is what has gone on before, that is, that which we remember, that which we CHOOSE to remember. It's fun and even educational to speculate what might have happened but it didn't. History is like the layers in the Grand Canyon, laid down in time for a time until it too is erased by time.

Had it not been for the Roman Empire, we might have had very different beliefs.

Well, that's fun, but that's not what happened. God as Author and Creator of all must see His story of Man as a complete work with no cone of probablility. He has already penned the last line. Plays havoc with "freewill" doesn't it? In chess, I believe the term is "Zugzwang" where the player has a limited number of moves, all of which lead to checkmate. This is how it must be for an omniscient God but not for limited Man. We keep thinking that WE are the masters of our destinies.