Statistics for occurrence #1 of “Mississippi River” in page 134 of John G. Nicolay, The Outbreak of Rebellion:

...secure all that were available, and the Richmond authorities now resolved to seize and hold Columbus, notwithstanding the fact that it lay in neutral Kentucky. Since July 4th the defence of the Mississippi River had been specially entrusted to General Leonidas Polk, formerly a bishop in the Protestant Episcopal Church, but who, since the outbreak of the rebellion, preferred to utilize his early West Point ed...
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