It therefore regards history in no small part as a succession of geographical factors embodied in events.

Back of Massachusetts' passionate abolition movement, it sees the granite soil and boulder-strewn fields of New England; back of the South's long fight for the maintenance of slavery, it sees the rich plantations of tidewater Virginia and the teeming fertility of the Mississippi bottom lands.

This is the significance of Herder's saying that "history is geography set into motion." What is to-day a fact of geography becomes to-morrow a factor of history.

The two sciences cannot be held apart without doing violence to both, without dismembering what is a natural, vital whole.
All historical problems ought to be studied geographically and all geographic problems must be studied historically.

Every map has its date.