In May 1863, Union Gen. Nathaniel Banks landed 30,000 soldiers at Bayou Sara north of Port Hudson, where a Confederate force of 7,500 men under Gen. Franklin Gardner held the Mississippi River stronghold. Banks's assault on May 27 failed, and nearly 2,000 soldiers died, including 600 men from the 1st and 3rd Louisiana Native Guards, among the first black soldiers to fight in the Civil War; their determination helped prove to the North that black soldiers could ably serve the Union cause. Banks then began a siege, built fortifications, brought up more artillery, and on June 14 launched another failed attack that caused about 2,000 more Union casualties. He continued the siege until July 9, when the Confederate garrison, reduced to eating mules and rats, surrendered. Over the 45-day siege, Banks lost about 10,000 men, half from disease, and the Union gained absolute control of the Mississippi River. In August 1866, Lt. A. Rayburn selected this site for Port Hudson National Cemetery on an 8-acre tract already used to bury Union soldiers who died there, and the government paid $3,000 for the land. Those buried here include 256 men who served in the United States Colored Troops, whose first regiments were formed in March 1863 as the federal government began actively recruiting black men for the Union Army; eight of those regiments fought at Port Hudson, and United States Colored Troops units served in battles from Virginia to Texas. By 1875, the cemetery contained 3,804 graves, most of them unknown, and remains from other places in Louisiana, including Morganza village, the Carnes Dunn's, Haynes, Slaughters, and Wilson's plantations, and Methodist College in West Baton Rouge Parish, were reinterred there. Early improvements included a brick wall around the cemetery and two gun monuments at the entrance road. In 1879, the Quartermaster Department built a brick Second Empire-style lodge for the superintendent and his family. Cast-iron plaques bearing stanzas from the poem "Bivouac of the Dead" were installed in the 1880s. The cemetery expanded twice in the twentieth century and now covers almost 20 acres.