At the turn of the 20th century, the city became a source of concern, something to study, something to ponder. On the back of the Industrial Revolution and the concurrent disappearance of older, more rural forms of life, millions of people in what is called “The West” began to move to urban centers. With Empire and imperialism at their height — recall that the Berlin Conference, where the imperial powers divided up Africa, happened only in 1884 — the city expanded and became the metropolis.