Ten image makers, from the diplomatic salons of Weimar Berlin to the gold mines of Brazil, who taught the world to get its news through a lens. For roughly seventy years, from the 1920s to the 1990s, the photograph was how the world found out what had happened.

For most of its history photography had to argue that it was an art at all. That argument is worth revisiting now, because the thing photography was defending has become scarce.