He attained this position from Colonel William B. Allison, then an aide to Governor Samuel J. Kirkwood, who would go on to have a successful political career as a Congressman in Washington, DC.

In 1862, he left Dubuque with the 12th Infantry to join the Army of the Potomac and saw action at Fredericksburg, Chancellorsville, Gettysburg, the Wilderness, Cold Harbor, and Spotsylvania.

In his letter to Belknap, Harlan wrote that Jackson, ..has been a citizen of Iowa for nearly fifteen years-has been an unflinching Republican from the organization of the party, is a true gentleman of irreproachable character-perfectly temperate using neither intoxicating liquors or tobacco in any form, and is the stay and support of his widowed mother in her old age.

Shortly afterwards, Jackson participated in the campaign against Captain Jack in the Modoc Indian War and commanded troops at the Battle of Lost River on November 28, 1872.

His commanding officer, Captain Randolph Norwood, had moved ahead of the main force under orders to find and engage the renegades, but were instead taken by surprise when the Nez Percé launched a frontal assault.

[2][3][6][7][8][9] The Nez Percé, wanting to return to Chief Joseph and their people as quickly as possible, escaped into the wilderness once the cavalry's horses and mules were secured.

Consequently, the recovered bodies of soldiers would frequently be found badly mutilated and Jackson hoped to spare his fallen comrade a similar fate.

As I was an eyewitness of the whole affair I feel it my duty to endeavor, even at this late day, to obtain for Captain (now Major) Jackson a proper recognition of an act of unusually distinguished gallantry displayed under circumstances making its performance much more noteworthy and hazardous than it could possibly be if dealing with an enemy governed by the rules of civilized warfare.

[1]Carr's request was initially declined by the then Acting Secretary of War who believed the incident occurred too long ago to merit issuing the award.

Citation: Dismounted from his horse in the face of a heavy fire from pursuing Indians, and with the assistance of 1 or 2 of the men of his command secured to a place of safety the body of his trumpeter, who had been shot and killed.