In February 1862, Union Gen. John Pope, then stationed in central Missouri, was placed in command of the 20,000-man Army of the Mississippi and ordered to advance on Island #10 and New Madrid. On February 28th, Pope and his men left Commerce, MO and marched south along the Sikeston Ridge through swamps, lugging supplies and artillery, reaching the outskirts of New Madrid on March 3rd and laying siege to the city. To advance successfully, Pope had to cut off routes of supply, because by capturing New Madrid he could bring the river under his guns and prevent enemy supply boats from reaching Island #10 from below. The Confederates had incorrectly assumed that Pope would not be able to haul heavy siege guns along the miry roads to the Federal entrenchments facing Forts Bankhead and Thompson and the Confederate gunboats protecting New Madrid's position. After 10 days of effort, on the 12th the Federals dragged four 128-pound siege guns, three 24-pounders, and an 8-inch howitzer on huge four-wheeled sling carts to New Madrid and began shelling the forts and gunboats. At dusk, Colonel James Morgan's brigade of Paine's division advanced to within eight hundred yards of Fort Thompson while troops worked through the evening on gun emplacements, trenches, and redoubts. By 3 am, the Federals had completed two redoubts with flanking rifle trenches for two regiments. Captain Joseph A. Mower, with two companies of the 1st US Infantry, manned the siege guns; the 10th and 16th Illinois held the trenches, supported by Bissell's engineers; seven companies of the 2nd and 3rd Michigan Cavalry anchored the far right beyond the breastworks; the 51st Illinois held the extreme left flank along the wooded slough from the river; Slack's brigade moved into a cornfield to the left of Cumming's regiment; and Stanley's Ohio division, backed by a dozen field guns, moved in the rear of the main line along the road, with more than ten thousand men deployed to support the siege batteries and Hamilton's division and Palmer's brigade in reserve. At dawn on March 13th, the opening fire took the Confederates completely by surprise, and unable to hold New Madrid against siege guns, Confederate commanders ordered the evacuation of the gunboat and their positions at Forts Bankhead and Thompson during the night in a rainstorm and much confusion. The next morning, Federals quickly occupied New Madrid and entered the deserted forts.
