u/Briyyzie

I have a little history project I want to work on. Where I live in the American West there are two larger cities, and sandwiched between them is a much smaller city. Despite the fact that it was settled earlier, had seemingly similar advantages ie railroad access and a river crossing, and often quite successfully jockeyed for position early on, it failed to grow to the same size or influence as the cities it lies between. I want to study why that is.

How do historians study and explain the forces that influence the rise, fall and evolution of cities? Understanding that would help me start.