John Alexander Campbell was born in 1843 at New York City in the United States. He worked as a farmer until his enlistment for military service at 18 years of age on July 29, 1861, at Indianapolis, Indiana. He signed as a Private up for a 3 year period with the 19^th Indiana Volunteer Infantry; part of the famous “Iron Brigade” under Captain John J. Clarke, and was mustered into Company G.

The 19^th Infantry Regiment was organized at Indianapolis, Ind., and mustered in July 29, 1861. It left Indiana  for Washington, D.C. on  August 5, 1861 and was attached to 3rd Brigade, McDowell's Division, Army of the Potomac until March 1862; during which it saw action at Lewinsville, Virginia on September 11, 1861 and participated in the occupation of Falls Church on September 28^th.   It was then transferred to the 1st Brigade, King's 3rd Division, 1st Army Corps, Army of the Potomac until April 1862, during which it advanced on Manassas, Viginia from March 10^th through the 16^th  and Falmouth, Virginia from April 9^th through the 19^th.   It was then attached to the 3rd Brigade, King's Division, Dept. of the Rappahannock, participating in McDowell's advance on Richmond from May 25^th through the 29^th remaining with the 3^rd until June, 1862. In June it was attached to the 4th Brigade, 1st Division, 3rd Army Corps, Army of Virginia and participated in operations against Jackson from June 1^st until the 21^st, remaining with the 4^th  until September of 1862;  moving to the  4th Brigade, Iron Brigade, 1st Division, 1st Army Corps, Army of the Potomac in September, remaining with it until June of the following year; 1863.

The 19^th Regiment continued in numerous battles and skirmishes including the Battles of the Wilderness, action at the Spottsylvania Court House, Cold Harbour and the Siege of Petersburg.  Non-Veterans mustered out July 28, 1864 and Campbell, remaining with the 63^rd until he received his discharge, received his on July 31, 1864; when he was mustered out at Hilton Head, South Carolina.

After the war, John resided at the National Military Home in Montgomery County, Ohio from where he applied for a disability pension, on May 13, 1876; stating that “while en route from Belle Plains, Virginia to Gettysburg in late June 1863” he had contracted “bronchitis and asthma from the weather, the hardships of heavy marching and privations incidental to that campaign during the months of May and June 1863”. He also contracted Typhoid Fever during July and October, while being treated at the Baptist Church Hospital and was transferred to a convalescent camp at Alexandria, Virginia; before being sent back to the 63^rd Company, 2^nd Battalion, Veterans Reserve Corps on October 1, 1864. After the war Campbell lived Indianapolis, Indiana and worked as a general laborer; when he was able to work.

Campbell first applied for a U.S. military pension May 13, 1876. At the time he was a resident of the National Military Home, a convalescent center for ailing soldiers, in Montgomery County, Ohio. He applied under the invalid soldiers act, application number 219507, which was then transferred to Washington for verification and approval.  In 1878, Pension Records state that John A. Campbell was then living in New York State. Consular Dispatches from Melbourne to the pension board reveal that he arrived at, or was already in,  Melbourne, Victoria, Australia by February 1894. He submitted additional invalid pension application papers to Washington, from Sydney, New South Wales in July 1904 and again in September 1912; using the U.S. Consulate in Sydney as his home address. His pension was finally approved and Campbell received $50 a month until October 5, 1923; when he died at the Rookwood State Hospital and Asylum in Sydney. John Alexander Campbell was laid to rest in Rookwood Cemetery, Church of England Section H, in Sydney, New South Wales.