Although I'm more than happy to talk about European economics, demographics, and development, I'm not quite sure what your parameter of reference is. France is about the size of the US state of Texas, but has more than twice the population; quite populous given the land-area. It is the second most populous nation in the European Union, only Germany is larger, and France is certainly within the same bracket of the other "large" european states (that is to say, Great Britain and Italy, which are both slightly smaller).

Is your question perhaps better framed as to why European states appear to be more culturally influential than many more populous countries?