Its origins were on May 4, 1861, when New Jersey was directed by the Federal government to fill a quota of three infantry regiments to serve a three-year term of enlistment.
Recruitment took place for the new regiments all over the state, and on May 21, 1861, the 1st New Jersey Volunteer Infantry was mustered into the Union Army at Camp Olden in Trenton, New Jersey, under Maj. Theodore T. S. Laidley of the United States Regular Army.
On June 28, 1861, the three newly created three-year regiments began the journey to Virginia, where in June they were joined with a brigade of three-month enlistment New Jersey Militia regiments to form a division commanded by Brig.
During the First Bull Run Campaign, most of the brigade saw service in the field guarding train hubs, supply depots and roadways, being considered too "green" to be reliable in combat.
As the war progressed, more regiments were added to the brigade, but in keeping with its tradition, they were New Jersey units.
The 4th New Jersey's men were subsequently released in a prisoner exchange and returned to their lines, but they lost the Model 1861 Springfield Rifles they'd been carrying.
It then fought in the Second Bull Run Campaign, where it blundered into the entire Confederate army corps commanded by Major General Stonewall Jackson, and at Crampton's Gap during the Battle of South Mountain, where it redeemed its honor by making a triumphant charge up the hill.
Later engagements included Fredericksburg, Chancellorsville, Gettysburg, the Wilderness, Spotsylvania, Cold Harbor, Strasburg, Fisher's Hill, and Cedar Creek.
Gen. Philip Kearny, whose training and discipline molded the regiments into an effective fighting unit.
After being mortally wounded at the Second Battle of Bull Run, the leadership of the brigade went to Alfred Thomas Torbert, who was serving as colonel of the 1st New Jersey Infantry.