Is there a place where I can order historical (political) maps of the world? e.g. a map of the roman empire, or what the world 'looked like' to the ancient Greeks, or how the world was divided in the 1800s etc. (?)
Google Images yields some results, but maybe there is a go-to website for this, and maybe there is even an online shop to order such maps from? Does anybody know? Wasn't able to find anything!
Libraries -- especially university libraries and larger public libraries -- usually have "historical atlases" that contain all sorts of maps of the kind you're looking for. Some of them may have been digitized, too. The library's catalog will tell you what the library has available for you in either print or electronic format. Or you can ask the reference librarian to show you what they've got.
Oldmapsonline.com and lib.utexas.edu are the ones i've used