Statistics for occurrence #1 of “lower Mississippi” in page 90 of The Photographic History of The Civil War: in ten volumes, Thousands of Scenes Photographed 1861-65, with Text by many Special Authorities, Volume 10: The Armies and the Leaders.:

...he lower South, and to exercise general supervision over the military operations in Tennessee, Mississippi, Alabama, and Arkansas, which were designed to make secure the hold of the Federals upon the lower Mississippi valley. The river was held, and the army of one hundred thousand men, under the immediate command of Sherman, carried to suchcess conclusion, in 1864-65, three campaigns—that against Atlant...
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