Assertion: photographer's photograph | /r/HasSubevent | the united states
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text: In the United States, photographs tracing the progress of the American Civil War (1861-1865) by photographers for at least three consortia of photographic publisher-distributors, most notably Mathew Brady and Alexander Gardner, resulted in a major archive of photographs ranging from dry records of battle sites to harrowing images of the dead by Timothy O'Sullivan and evocative images by George N. Barnard.