Comte de Paris, History of the Civil War in America. Vol. 1.
Henry Coppee , LL.D., Ed.

Hostilities, therefore, broke out everywhere at once. At nearly every point of the territory isolated individuals, small groups, or numerous bands began to make war on their own account, seeking only to satisfy personal hatred. There was no longer safety to be found anywhere. Blood flowed in every spot, and it became impossible to discriminate between an act of war and assassination. Missouri, however, notwithstanding her isolation, was not neglected by the belligerents. They had little cause to trouble themselves about what was taking place in the western part of that State, but all that portion of it adjacent to the Mississippi was to play a great part in the military operations of which the line of that river was about to be the theatre. The Federals could undertake no expedition, either into Kentucky, by ascending the Tennessee, or against Memphis and the heart of the Confederacy, unless they were masters of the confluence of the Missouri and the Ohio with the Mississippi—that is to say, of St. Louis, of Cairo, and of that portion of the river which separates those two points. The left bank was secured to them, for it belonged to Illinois; to control the right bank, generally flat and marshy, it was necessary, in the first place, to occupy strongly the large city of St. Louis, the base of operation of all water expeditions into the centre of the continent; then to prevent the enemy from taking possession of the cliffs of Cape Girardeau, whence he could have intercepted the navigation of the river, and from occupying the positions of Bird's Point which command the tongue of land upon which Cairo stands. General Lyon, as we have seen, had preserved the city of St. Louis to the Union, and Cairo had been garrisoned by Federal troops before the Confederates had made any attempt to seize it. But the secessionists, on seeing the best portion of the State slipping away from them, no longer contented themselves with waging a partisan war. At the call of Sterling Price all those who had made the long Mexican campaigns with him or with Doniphan, or who had many times listened to the exaggerated descriptions given of them, hastened to form themselves into an army, intended to recapture the State from the Federal troops, under the name of ‘Missouri Guards.’