Once committed to the scheme, Banks devoted himself loyally to the arrangements necessary for prosecuting it on a scale at least commensurate with the magnitude of the undertaking and with the expectations of the government, as he understood them. Texas was to be his objective, and he was the lead his army up the Red River, as the shortest and best way to Texas. From the outset he was committed to the use of a large body of cavalry able to operate on the plains that lie beyond the Sabine, as well as to overcome the opposition of the mounted forces of the Confederacy in that region. Not only was forage scarce in the Red River country, but Shreveport once taken and passed, the march would lie for three hundred miles across a desert; an immense forage train was therefore indispensable. It was also reasonable to suppose that, before passing Shreveport, the combined armies of the Confederacy in the trans-Mississippi would have to be met and beaten, and for this end a large force of infantry and artillery must also form part of the expedition, at least as far as Shreveport. The co-operation of the Navy was necessary, in its turn, if only to keep open the long line of supply by the Red River. Finally the usual time of the highest water in the upper Red River fixed the date of the movement.
Sherman came from Vicksburg to New Orleans on the 1st of March, and within a few hours reached a distinct agreement with Banks as to the aid expected from the Army of the Tennessee. Admiral Porter had already arranged to be at the mouth of the Red River with a large fleet of gunboats in time for the rising of the waters; and now Sherman promised to send with the fleet ten thousand picked men of his army, to be at Alexandria on the 17th of March. Banks, on his part, agreed that his troops, marching north by the Teche, should meet Sherman's at Alexandria. Steele, who was at Little Rock, undertook to move at the same time to meet the combined forces and the fleet on the Red River. Confronting Steele was Price; across Banks's line of advance stood Taylor; with the whole or any part of his force, Sherman and Porter might have to reckon, and in any case Fort De Russy must be neutralized or reduced before they could get to Alexandria.