Milo S. Hascall was born in LeRoy in Genesee County, New York. In 1846 he moved to Goshen, Indiana, where he clerked in a store and taught school. Two years later, he was appointed as a cadet at the United States Military Academy, graduating in 1852. He was assigned as a second lieutenant in the 2nd U.S. Artillery and was stationed in New England doing garrison duty in Newport Harbor, Rhode Island. After a year of service in the Regular Army, he resigned his commission. Hascall went back to Goshen, where he became a lawyer and filled various political offices. He also was a railroad contractor, district attorney, and the clerk of the county courts. He practiced law in Goshen, Indiana, from 1855 till 1861, serving as prosecuting attorney of Elkhart and Lagrange counties from 1856 till 1858, and school examiner and clerk of courts from 1859 till 1861.
At the outbreak of the Civil War, he enlisted as a private, but was soon appointed aide-de-camp to General Thomas A. Morris, with the rank of captain, and assisted in organizing six volunteer regiments. On June 12, 1861, he was made colonel of the 17th Indiana Infantry and took part in the successful West Virginia campaign under Major General George B. McClellan. In December 1861, he was ordered to Louisville, Kentucky, and placed in command of a brigadeconsisting of the 17th Indiana, 6th Ohio, 43d Ohio, and 15th Indiana regiments, assigned to the division commanded by General William "Bull" Nelson. Later that month, he was given charge of a brigade in Thomas J. Wood’s division of Don Carlos Buell’s forces in the Army of the Ohio. His troops arrived at Shilohthe day after fighting ended, but did take part in the Siege of Corinth. Hascall was commissioned as a brigadier general of volunteers on April 25, 1862. Having been transferred to the Army of the Cumberland, he was put in command of a brigade which fought through the Kentucky Campaign. He continued to serve in Tennessee through March 1863. During the Battle of Stones River, he assumed command of the 1st Division when General Wood was wounded. During the battle, Hascall led reinforcements to the Round Forest where he took charge of the defense of that place and decided it had to be held at all costs. After the battle he was sent to Indianapolis, Indiana, to take command of the District of Indiana, charged with returning deserters from Ohio, Illinois, and Indiana. He also suppressed dissident opinions in Indiana newspapers, including the Plymouth Democrat. He then was transferred to the Army of the Ohio and placed in command of the 3rd Division in the XXIII Corps. Later that year, he took part in the battles the defense of Knoxville. The next year Hascall commanded the 2nd Brigade, 2nd Division, XXIII Corps for the first part of the Atlanta Campaign. During the battle of Resaca 2nd Division commander, Brig. Gen. Henry M. Judah failed to reconnoiter a river valley to his front before attacking. During the attack Hascall's brigade accidentally crossed in front of Brig. Gen. John M. Palmer's division before it deployed. Despite both units becoming intertwined, Judah pushed Hascall forward only to have his men get stuck in the muddy creek. On May 18 Hascall assumed command of the 2nd Division after General Judah was relieved of command. Hascall led the division throughout the rest of Atlanta Campaign.
Postbellum career
He resigned on October 27, 1864, and returned to Goshen, where he engaged in banking, but later entered the real-estate business in Chicago, Illinois. He was buried at Forest Home Cemetery, in Forest Park, Chicago.
