When MG William S. Rosecrans formed the Pioneer Brigade in November, 1862 to alleviate deficiencies in his engineer organization he needed an experienced engineer officer to take command. The task fell to Captain James St. Clair Morton. Rosecrans was intrigued by the young engineer Morton for his “iconoclasm, outspoken individualism and willingness to challenge engineer dogma.”
Morton was wunderkind of a sort, entering the University of Pennsylvania at age 14. At 18 he received a West Point recommendation and completed the course of study in 1851, finishing second in his class. His high class standing afforded him an appointment to the Corps of Engineers. His first assignment was as assistant engineer of construction for forts at Charleston, SC, including Fort Sumter. Following an assignment at Fort Delaware he returned to West Point as an instructor in mathematics and military engineering. The audacious Morton began writing essays to Secretary of War John Floyd concerning Dennis Hart Mahan’s principles. Impressed, Floyd asked Morton to evaluate Colonel Joseph Totten’s, Chief Engineer for the Corps of Engineers, for the defense of New York City. Morton placed himself at odds with his superior by dismissing stone forts in favor of earthworks. Nevertheless, Morton was promoted to 1st Lieutenant and assigned work on the Sandy Hook Lighthouse in New Jersey, the Washington Monument, and the capital’s water works.
Choice assignments continued to come his way in 1860 when he was selected to command a detail going to Central America to determine the feasibility of a canal across the isthmus. While there he contracted malaria and returned to the US. He departed Washington in March of 1861 for the Florida Keys to work on Fort Jefferson. A recurring bout with malaria sent him back to Washington to recover. In May 1862 he was assigned as Chief Engineer to the Army of the Ohio. At Nashville he supervised the construction of Fort Negley.
When MG Don Carlos Buell was replaced by Rosecrans, Morton was promoted to Brigadier General of Volunteers to command the newly formed Pioneer Brigade. During the Battle of Stones River the brigade found itself in the middle of the action. The Pioneers won fame by holding the Union line against a Confederate attack. After the battle Morton was placed in charge of construction of Fort Rosecrans, the largest such project of the war. Following the loss at the Battle of Chickamauga the brigade fell victim to excuse seekers. The Pioneer Brigade was criticized for interfering with critical movements. Morton was summoned to Rosecrans headquarters and given a severe tongue lashing in front of several other officers. Embarrassed and disgusted Morton sought transfer. Denied he was sent to Nashville to work on defenses there. He eventually asked that his volunteer commission be stripped away and he be returned to his Regular Army rank of major, becoming the only officer to give up generals stars willingly.
After a brief stay in Washington he returned to the front as Chief Engineer of Ambrose Burnside’s IX Corps outside of Petersburg. Writing his report of the Fifth Epoch of the Overland Campaign on October 20, 1864 Campaign Major Nathaniel Michler noted:
“The Engineer Corps was called upon, on the 17th (June), to mourn the loss of one of its most accomplished officers. While reconnoitering the position in front of Ninth Corps for the purpose of selecting the ground upon which a division (Orlando Wilcox) in line of battle preparatory to the assault of that day, Major Morton exposed himself to the unerring shot of one of the enemy’s sharpshooters. He was killed instantly, the ball penetrating his left breast.”
He is buried in Laurel Hill Cemetery in Philadelphia. Another of the best and brightest to fall.
 The Pioneer Brigade, Geoffrey Blankenmeyer  OR, Vol. 40