The Siege of Port Hudson, Louisiana (May 22–July 9, 1863) was one of the most important campaigns of the American Civil War. Together with the fall of Vicksburg on July 4, 1863, the capture of Port Hudson gave the Union complete control of the Mississippi River, dividing the Confederacy and severing the Trans-Mississippi states from the rest of the South.

The 10th Arkansas Infantry, organized in July 1861, had previously fought at Shiloh and Baton Rouge before becoming part of Major General Franklin Gardner's garrison at Port Hudson. During the siege, the regiment defended the Confederate earthworks against repeated Federal assaults on May 27 and June 14, 1863. Heavy casualties, dwindling supplies, and declining morale plagued the regiment throughout the 48-day siege. Internal dissension became so severe that several companies refused to rotate into the trenches, resulting in the arrest of Lieutenant Colonel E. L. Vaughn just days before the surrender. When General Gardner capitulated on July 9, the officers and men of the 10th Arkansas became prisoners of war, although many enlisted men were later paroled and eventually reorganized in Arkansas.

The 75th New York Infantry, recruited primarily from central New York and known as the "Auburn Regiment," served in the Union XIX Corps under Major General Nathaniel P. Banks. During the Port Hudson Campaign, the regiment fought at Fort Bisland before participating in both major assaults against the Confederate fortifications on May 27 and June 14, 1863. The 75th suffered heavily, losing more than 100 officers and men killed, wounded, or missing during the assaults, a testament to the ferocity of the fighting. Following the Confederate surrender on July 9, the regiment remained on garrison duty at Port Hudson before continuing operations in Louisiana