While it is true that in the beginning, at his own expense, the enterprising Mathew Brady secured the necessary permissions from the War Department for the purpose of documenting the "rebellion", it would be others, particularly those photographers who were under the direct supervision of, or were employed by Alexander Gardner, such as Timothy O'Sullivan, James Gibson, George Barnard, James Gardner and William Pywell, who would follow the armies and ultimately fulfill the difficult task of recording for posterity a timely, consecutive photographic history of the American Civil War.