At the time of General Grant's appointment, the Western Department, which included all the region between the Mississippi and the Rocky Mountains, with the State of Illinois and such parts of Western Kentucky and Tennessee as might be in possession of the national arms, was under command of General Fremont. For his own convenience, the chief of this department divided his territory into sub-districts; and on the 1st of September Grant was ordered to the command of the South-east Missouri District, including Western Kentucky and Tennessee. On the 4th of the month he established his headquarters at Cairo. General Grant was now in a position to make himself felt, and he began to gaze out upon the broad field of Southern aggression before him. He was on the actual dividing line between loyalty and rebellion, prepared to defend the one and invade the other. Governor Magoffin, of Kentucky, had made his sensational reply to the call for troops, that his state would furnish none for the "wicked" purpose of subduing her sister Southern States, and had issued his proclamation of neutrality, which meant nothing but rebellion, as proved by the subsequent conduct of the man. There could be no neutral state between the fiery South and the indignant North. Cairo was a point of the utmost importance to the loyal cause, as a depot of supplies, as a gunboat rendezvous, and as a strategetic position. The Mobile and Ohio Railroad extended through the western part of Tennessee to the northern line of that state, where it diverged into three branches, terminating respectively at Hickman, Columbus, and Paducah, connecting these places with all the principal cities of the South, each of which might form a base of operation for offensive movements on the part of the rebels. Neutrality in Kentucky meant rebellion. It was proclaimed in the interests of the South, but it was not, and could not be, respected by either party. It was first violated by the rebels, who failed to sound the notes of indignation when Bishop General Polk marched his army into the state and seized upon Hickman and Columbus. General Grant had studied his maps faithfully, and fully comprehended the situation, not only in its present but in its future significance. Polk was in full march upon Paducah, the possession of which would give the rebels the control of the navigation of the Ohio and the entrance of the Tennessee, at the mouth of which the town is located. Grant was wide awake, and a few days after he had established his headquarters at Cairo he completed his hasty preparations for the capture of Paducah, and started late in the evening with two regiments and a light battery, with two gunboats--the naval force of his district having also been placed under his direction. Arriving at his objective point the next morning, he landed his force, and took possession of the town, the rebels under Tilghman hastily evacuating the place while the national troops were landing.