Robert Johnston was a colonel in the Confederate Army, serving in the 3rd Virginia cavalry. Johnston was born in Virginia c.1826. He completed his doctoral thesis from the University of Maryland’s medical school in 1852 after graduating from West Point in 1850. Johnston then joined the United States military and, from 1851-1856 and 1858-1861, served on frontier duty with the 1st Dragons as a first lieutenant. At the outbreak of war, he resigned from the Northern Army in April 1861 and joined the Virginia 3rd Cavalry as a colonel the following month. The cavalry was part of the Army of Northern Virginia which served under J.E.B. Stuart and Colonel Thomas H. Owen. After Gettysburg, he served under George Pickett. At the end of the war, Johnston was taken as a prisoner and sought amnesty by signing the loyalty oath "not to take part in hostilities against the Government of the United States."
In 1857, Johnston married Catherine Van Rensselaer, daughter of John Sanders Van Rensselaer and Ann Dunkin of Albany, New York. During the war, Catherine remained in Albany at her father's house with their two young children Robert and Dunkin (they had eight children over the course of their marriage). Johnston died in New York on July 2, 1902.
From the guide to the Robert Johnston papers, Johnston, Robert papers, 1863-1865, (William L. Clements Library, University of Michigan)
