The campaign for the control of Vicksburg was one of the most important contests in determining the outcome of the Civil War. As President Abraham Lincoln observed, “Vicksburg is the key. The war can never be brought to a close until that key is in our pocket.” The struggle for Vicksburg lasted more than a year, and when it was over, the outcome of the Civil War appeared more certain.
Additional resources about the American Civil War maybe found at Hot Topics – American History.
Also read the newspaper accounts of the battle in the Historical New York Times. Just enter the search terms vicksburg campaign. You can also scope the articles down by adding a publication date range. For example: 11/01/1862 to 07/31/1863: