|Name at Enlist||Osmund Petersen|
|Birth Name||Amund Sivle|
|Other Names||Osmund (Aamund) Petersen (Peterson)|
|Lived||ca. 1841 -|
|Residence at Muster-In||Chicago, Cook County, IL|
|Company at Enlistment||A|
|Rank at Enlistment||Private|
|Muster Date||15 Nov 1861|
Amund Pedersen Sivle was enlisted under the name Osmund Petersen in Company A of the 15th Wisconsin by Captain Andrew Torkildson. He joined up in Chicago, Cook County, IL, on October 26, 1861, for a 3-year term of service. The men of the company called themselves the "St. Olaf's Rifles." They were also known as the "Sailor Company" because of the large number of seamen in its ranks, and as the "Chicago Company" because so many of its members were residents of that city. Osmund was mustered into Federal service as a Private (Menig) on November 15, 1861, at Camp Randall near Madison, Dane County, WI. At the time he was 21 or 22 years old and not married. His residence was listed as Chicago, IL.
Private Petersen was appointed as the 1st Corporal (Korporal) of Company A on January 1, 1862. On January 14, 1862, the men of the 15th were issued Belgian rifled muskets. After about 15 weeks at Camp Randall learning to be a soldier, Corporal Petersen left there in early March 1862, with his company and regiment to join the war. From then until December 1862 he was listed as "present" with the 15th. As such he would have participated in the successful siege of Island No. 10 on the Mississippi River in Tennessee and the surprise raid on Union City, TN, in March and April 1862. That summer he would have been with the 15th on the campaign though Tennessee, Mississippi, and Alabama. In August and September he would have participated in the grueling 400-mile retreat with General Buell up to Louisville, KY, with the last 2 weeks being on half rations and short of water.
Corporal Petersen would have also been present at the October 8, 1862 fighting at Perryville, Boyle County, KY, which was also called the Battle of Chaplin Hills. While this was the 15th's first big battle, it emerged without any fatalities. On November 1, 1862, Corporal Petersen was appointed to the rank of Sergeant (Sersjant) in Company A.
In late December, Sergeant Petersen would have participated in the 15th's desperate charge upon a Confederate artillery battery at Knob Gap, TN, just south of Nashville. There the 15th captured a brass cannon. He is known to have fought at the long, cold, wet, and bloody Battle of Stone River, TN, also called the Battle of Murfreesboro, at the end of December 1862. It is there that the 15th first suffered serious battle casualties, and was cited for bravery. On the second day of the battle, Sergeant Petersen was "wounded in thigh." He was then sent to a hospital at the "west end" of Cincinnati, OH, to recover.
Sergeant Petersen was again present with the 15th starting sometime in March or April 1863, when it was camped near Murfreesboro, TN. On June 23, 1863, the regiment left there to take part in General Rosecrans' Tullahoma campaign. On July 3, 1863, the 15th went into camp for 6 weeks in Winchester, Franklin County, TN.
On August 17, 1863, the 15th left Winchester to participate in General Rosecrans' Chickamauga campaign. Sergeant Petersen is believed to have been present at the daring early morning crossing of the Tennessee River on August 28th, which the 15th led. He was present at the September 19-20, 1863 fighting at Chickamauga, GA -- the second bloodiest battle of the Civil War. There Sergeant Petersen was "wounded in left hip and captured" during the vicious fighting around Viniard's Farm on the first afternoon of the battle. Some 63% of the 15th's soldiers who were at Chickamauga were killed, wounded, or taken prisoner.
Sergeant Petersen was one of the very luckiest of the many 15th soldiers captured. He was paroled back to Federal authorities at Chattanooga, TN, on September 29, 1863. Most of his comrades who were captured were sent to Confederate prisons, including the dreaded Andersonville Prison Camp. Many died as prisoners. The ones who survived were often physically and mentally injured by their experiences.
After being paroled, Sergeant Petersen was "sent to Nashville to be exchanged." Due to the severity of his wounds, Sergeant Petersen was never able to return to the regiment. Instead he was discharged from the Army due to his disabilities at the City General Hospital in Chicago, IL, on either July 28 or August 10, 1864. Sergeant Petersen's Certificate of Disability for Discharge describes him as having been born in Norway, standing 6 feet tall with blue eyes, light complexion, and auburn hair, and was a sailor when he enlisted.
Sources: Civil War Compiled Military Service Records by Office of Adjutant General of the United States (Washington, DC); Det Femtende Regiment, Wisconsin Frivillage [The Fifteenth Regiment, Wisconsin Volunteers] by Ole A. Buslett (Decorah, Iowa, 1895); Regimental Descriptive Rolls, Volume 20, Office of the Adjutant General State of Wisconsin (Madison, Wisconsin, 1885); and, Roster of Wisconsin Volunteers, War of the Rebellion, 1861-1865, Volume I, Office of the Adjutant General State of Wisconsin (Madison, Wisconsin, 1886).