Comte de Paris, History of the Civil War in America. Vol. 3.
Henry Coppee , LL.D., Ed.

His position was indeed becoming critical. The railroad from Jackson to Grenada passes by Carrollton, within reach of Greenwood. By this route, as well as by that of the Yazoo, where he had several vessels, Pemberton could rapidly transport a sufficient number of troops to Greenwood to crush Ross' small division, isolated as it was and out of reach of any assistance. Several regiments had already left Vicksburg, and a few batteries placed along the Cold Water could bar the passage to the Federals, who were too far away from the Mississippi to reach it by any land route.

As soon as Grant became aware of Ross' situation he determined to make a diversion in his favor which might possibly open another route to Yazoo City, and which would, at all events, give Quinby time to join the expedition with sufficient forces to extricate it.

The indefatigable Porter, finding that the great overflow in the beginning of March was destroying all the works of Williams' channel, thought that if it closed the route against him on one side, it might, in return, open a pass in the labyrinth of bayous bordering the mouth of the Yazoo for debouching into this river between Yazoo City and Haines' Bluff. A reconnoissance made in Steele's Bayou, which ordinarily is only a large ditch, where he found five fathoms of water, had convinced him that the undertaking was worth a trial. He had immediately organized an expedition composed of his best and most powerful ships, such as the Louisville, the Cincinnati, the Carondelet, the Mound City, the Pittsburgg, four mortar-boats, and four tow-boats. Grant had accompanied it on the 14th as far as Steele's Bayou. On his return to Milliken's the general-in-chief was informed at the same time of the repulse sustained by the gunboats on the Tallahatchie and the movements of the enemy in the direction of Greenwood. He immediately ordered Sherman to follow Porter, to support and assist him in reaching the Yazoo. Once in the waters of this river, the Federal fleet could have destroyed all the enemy's vessels that happened to be there, taken Greenwood in the rear, and made navigation safe as far as Yazoo Pass. Sherman, resting on this new base, would have been able to take a strong position on the border of the Yazoo, and crossed this river in order to turn Haines' Bluff.