Krupp Smokestacks in Essen (1867) As seen in this 1867 photograph, smoke emanating from the gigantic smokestacks of the Krupp firm in Essen added to the air pollution that afflicted the Ruhr district in the 19th and 20th centuries – and still does today, despite the advent of the ecological movement in the 1970s, the passing of meaningful environmental protection legislation in the 1980s, and the new political influence of the Green Party since the 1990s.