2nd Wisconsin Volunteer Infantry Regiment The 2nd Regiment Wisconsin Volunteer Infantry was an infantry regiment that served in the Union Army during the American Civil War . It spent most of the war as a member of the famous Iron Brigade of the Army of the Potomac . Service . The Governor of Wisconsin , Alexander W . Randall ( R ) , issued a call to arms throughout the state of Wisconsin following President Abraham Lincoln ' s April 15 , 1861 , proclamation for troops to put down the rebellion . Enough Wisconsin men enrolled to allow the formation of two regiments , one more than the single regiment quota from Lincoln ' s directive . The 2nd Wisconsin was primarily raised in Madison , Racine , Milwaukee , Oshkosh , and La Crosse . It assembled in Madison and was mustered into Federal service on June 11 , 1861 , as a three years regiment ( reorganized from the original three months regiment ) . Governor Randall commissioned S . Park Coon , a 41 - year - old native of New York and Wisconsin ' s attorney general prior to the war , as the new regiment ' s first colonel . The lieutenant colonel , Henry W . Peck , was an Ohioan who had graduated from West Point in 1851 and provided some professional military experience and training , versus the political appointee Coon . The regiment was transported to Washington , D . C . , and saw its first combat at the First Battle of Bull Run in July 1861 in a brigade under William T . Sherman . Coon , never comfortable in his role as a military man , resigned July 30 to return to politics . Peck and the major also resigned , all were considered victims of the regiment ' s poor performance at Bull Run . Three new field officers replaced them — Col . Edgar O ' Connor , Lt . Col . Fairchild , and Maj . Thomas S . Allen . The appointment of O ' Connor , married to a Southern woman and an outspoken Democrat , was met with sharp criticism in Wisconsin ' s media , particularly in the Republican newspapers . He would prove to be a brave and competent leader , however , and was killed in action in Virginia in late summer 1862 . Lt . Col . Fairchild was promoted to the rank of full Colonel on September 8 , 1862 to become the third Commander of the 2nd Wisconsin Volunteers . The regiment suffered severe casualties during the 1862 Northern Virginia Campaign , fighting against Stonewall Jackson ' s Confederates at the Battle of Groveton , and seeing more action at the Second Battle of Bull Run . During the subsequent Maryland Campaign , the 2nd Wisconsin attacked Turner ' s Gap during the Battle of South Mountain , and then again took high casualties in the Cornfield at Antietam . Perhaps the regiment ' s finest hour came at Gettysburg , where it lost 77 % of its strength ( 233 casualties out of 302 effectives ) in stubborn fighting on McPherson ' s Ridge during the Iron Brigade ' s lengthy action on July 1 , 1863 . Colonel Fairchild lost an arm due to severe wound , and most of the line officers went down as well . The regiment reformed on Culp ' s Hill and entrenched for the rest of the battle . It later served in the Bristoe and Mine Run Campaign s . Although the 2nd Wisconsin was able to replenish some of its losses , it was never the same fighting force again . The regiment was mustered out on July 2 , 1864 . New recruits and later enlistees were consolidated into a battalion which was amalgamated with the 6th Wisconsin Volunteer Infantry Regiment on November 30 , 1864 . Total enlistments and casualties . The 2nd Wisconsin Infantry initially mustered 1051 men and later recruited an additional 152 men , for a total of 1203 men . The regiment lost 10 officers and 228 enlisted men killed in action or who later died of their wounds , plus another 77 enlisted men who died of disease , for a total of 315 fatalities .