When the Civil War erupted in April 1861, many German immigrants in Illinois rushed to enlist in the Union Army. Volunteers from Illinois towns in St. Clair County—Belleville, Millstadt, Mascoutah, Lebanon, and others—marched to Springfield under the command of August Mersy, a veteran of the failed 1848 revolt in Baden, Germany.

Marion Morrison notes that when the German immigrants reached Springfield, August Mersy was rejected as commander because of his limited facility with English. Replaced by Colonel Eleazer A. Paine, an Ohioan and West Point graduate, Lieutenant Colonel Mersy fell to second in command of the Ninth Illinois Infantry Volunteers. Within a few months, however, Paine received a promotion to general that left Mersy in charge of the "Bloody Ninth."

Once Grant began his Tennessee River campaign, the Ninth found itself in the thick of battle, bearing the brunt of the Confederate attempt at Fort Donelson to break Grant’s siege lines. Less than two months later, the Ninth shored up sagging Union lines after the surprise Confederate attack at Shiloh Church, retreating only when their ammunition was gone.

Morrison’s account of the "Bloody Ninth" is one of the few histories written during the war.