Lewis Hamilton, his team mate and only real title rival, finished third after starting in 20th place and then charging through the field on an overcast afternoon that threatened rain without delivering.
Finland's Valtteri Bottas took second place for Williams, his third podium finish in a row, after Brazilian team mate Felipe Massa crashed at the start in a collision that brought out the safety car.
Rosberg's win was the first for a works Mercedes team in Germany since Argentine Juan Manuel Fangio in 1954 and his fourth victory of the season.
Image: Nico Rosberg
Photograph: Dan Istitene/Getty Images
Rosberg on pole for his home German GP
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