At Crystal Springs, Mississippi, Jerome Bonaparte Yates enlisted on April 25th, 1861, a little more than a week following the firing on Fort Sumter. He would join Company C, called the “Crystal Springs Southern Rights”, of the 16th Mississippi Infantry, eventually rising through the ranks to Sergeant. The 16th Mississippi was sent to Virginia in June 1861, and would spend the rest of the war fighting in the Eastern Theatre. The regiment suffered heavily at the Battle of Sharpsburg (Antietam) on September 17th, 1862 and the Battle of Spotsylvania Court House at the Bloody Angle on May 12th, 1864. Jerome was captured at the Battle of Weldon Railroad on August 21st, 1864, but was soon exchanged a month later and returned to the 16th Mississippi. Other than brief periods of sickness, Jerome was present on most muster rolls.

When the Federal armies broke through the Confederate defensive lines around Petersburg on April 2nd, 1865, the members of the 16th Mississippi were defending Fort Gregg, trying to slow down the Union soldiers. Called the Confederate Alamo by some, Federal troops assaulted the 330 Mississippians defending the walls and parapets. Fighting soon turned bloody and savage, and the Mississippians did not want to give up the fight. According to Captain A. K. Jones of the 12th Mississippi Infantry, “The slaughter was appalling. I saw the field at Fredericksburg, Chancellorsville, the Wilderness, and the 12th of May, 1864, at Spotsylvania Court-house, and at neither place were the dead half so thickly strewn as at Gregg.” However, numbers soon prevailed for the Union forces as they committed more men to the fight, and they were able to overwhelm the defenders. Many from the 16th Mississippi sacrificed themselves at Fort Gregg to buy time for the rest of General Robert E. Lee’s army to escape. Jerome escaped that fate whether by escaping in the aftermath of the fight or he may have not been present. Either way, with the survivors of the 16th Mississippi, he retreated with the rest of Lee’s army westward from Petersburg, hoping to make it to North Carolina to join up with another Confederate army under the command of General Joseph Johnston. Lee would be stopped a week later at Appomattox Court House. Surrounded on three sides by Federal soldiers and the fourth by the flooded James River, Lee surrendered the Confederate Army of Northern Virginia on April 9th, 1865. Jerome was one of 4 officers and 68 men to surrender at Appomattox.