Statistics for occurrence #1 of “Mississippi River” in year 1863, month July, day 27 of Rebellion Record: a Diary of American Events, Diary from December 17, 1860 - April 30, 1864:
...venth regiment of Connecticut volunteers returned to New Haven.--A. Salute of one hundred guns was fired at Boston, Mass., in honor of the victories at Port Hudson, Vicksburgh, and the opening of the Mississippi River .
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