The Anaconda Plan was a strategy outlined by the Union Army for suppressing the Confederacy at the beginning of the American Civil War. Proposed by Union General-in-Chief Winfield Scott, the plan emphasized a Union blockade of the Southern ports and called for an advance down the Mississippi River to cut the South in two. Because the blockade would be rather passive, it was widely derided by a vociferous faction of Union generals who wanted a more vigorous prosecution of the war and likened it to the coils of an anaconda suffocating its victim. The snake image caught on, giving the proposal its popular name.
In the early days of the Civil War, Scott's proposed strategy for the war against the South had two prominent features. First, all ports in the seceding states were to be rigorously blockaded. Secondly, a strong column of perhaps 80,000 men should use the Mississippi River as a highway to thrust completely through the Confederacy. A spearhead, a relatively small amphibious force of army troops transported by boats and supported by gunboats, should advance rapidly, capturing the Confederate positions down the river in sequence. It would be followed by a more traditional army, marching behind to secure victories. The culminating battle would be for the forts below New Orleans. When they fell, the river would be in US hands from its source to its mouth, and the rebellion would be cut in two.
Origin of plan
The Anaconda had a logical development, both in its origin and the way it played out in the experience of battle. The blockade had already been proclaimed by Lincoln. On April 19, 1861, a week after the bombardment of Fort Sumter that marked the outbreak of the war, he announced that the ports of all the seceded states, from South Carolina to Texas, would be blockaded; later, when Virginia and North Carolina also seceded, their coastlines were added. The executive order was not rescinded until the end of the war and so the blockade existed independently of Scott's plan.
In the early days of the secession movement, the status of the border states Missouri, Kentucky, Maryland, and Delaware, all of which allowed slavery, was unclear. All except Delaware had strong pro-Southern interests. Missouri was torn by internal conflict that mimicked in miniature the larger war that was convulsing the nation, Maryland was kept in the Union by jailing many of the opposition faction, and Kentucky tried to keep the peace by proclaiming its neutrality by aiding neither the North nor the South if both would agree to leave the state alone.
Because Congress was not in session to authorize presidential initiatives to suppress the rebellion, the burden of raising troops for the war fell on the loyal state governments. Ohio was particularly active in doing so and early acquired the services of George B. McClellan, who was to serve as the commander of its militia, with rank Major General of Volunteers. In a few weeks, as the state militias were incorporated into the national service, the militias of Indiana and Illinois were added to his command. From this power base, he felt enabled on April 27, 1861, to write a letter to General Winfield Scott outlining his strategy. He proposed an immediate march on Richmond, by now the capital of the Confederacy, directed up the Kanawha River. Alternatively, if Kentucky were to leave the Union, a march directly across that state should take Nashville, and then, he would "act on circumstances."
Scott's endorsement of McClellan's letter, which he submitted to the President, shows that he considered it but not favorably. Firstly, the Kanawha was not suited for water transport and so the march on Richmond would have to be overland and thus subject to breakdowns of men, horses, and equipment. More seriously, western Virginia (West Virginia had not yet parted from Virginia) was still very much pro-Union; according to Scott's estimate, its populace stood five out of seven opposed to secession. An invasion as proposed would alienate many of them and subject both enemies and friends to the ravages of war. The same argument could be applied to Kentucky. Perhaps most damagingly, the war as proposed would subjugate the Confederacy piecemeal, with by necessity the border states bearing most of the burden, "instead of enveloping them all (nearly) at once by a cordon of ports on the Mississippi to its mouth from its junction with the Ohio, and by blockading ships on the sea board."
The germ of Scott's Anaconda Plan for suppressing the insurrection is seen in the endorsement. After giving the plan more thought he submitted his own proposal in a letter to McClellan on May 3, 1861. A second letter, dated May 21, was his final outline of the plan.