In the video below the folks of RealLifeLore give a short summary of the history of the territorial expansion of mankind.

Given our nature as an expansionist species it seems to be inevitable we will eventually settle the world’s oceans, Antarctica and, of course, Outer Space.

On a loosely related notice, Margaret Kohn and Kavita Reddy have written an article on the Stanford Encyclopedia of Philosophy on the historical attempts to justify colonialism. They also spend some time explaining the difference between colonialism and imperialism.