Dandridge McRae was born on 10 October 1829 in Baldwin County, Alabama. McRae graduated from South Carolina College in 1849.
McRae moved to Searcy in White County, Arkansas. He was admitted to the bar and served as clerk of the county and circuit courts for six years. In 1861 when Arkansas seceded from the Union he was Inspector General of Arkansas. He entered the Confederate Army as a Major in command of the 3rd Arkansas Infantry Battalion.
McRae recruited, trained, and organized soldiers for the Confederacy and raised the 21st Arkansas Infantry Regiment and was soon elected Colonel of that unit. McRae and his regiment participated in the Battle of Wilson's Creek under General Ben McCulloch.
McRae and his regiment took part in the Battle of Pea Ridge in March 1862 and received commendations from commander Earl Van Dorn. McRae remained in Arkansas while most troops were moved eastward across the Mississippi River and participated in operations there. On 5 November 1862 he was commissioned as Brigadier General.
In 1863 McRae and his command took part in the Battle of Helena in a failed effort to secure that river port for the Confederacy.
During the Red River Campaign McRae formed part of the force under General Sterling Price and participated in the Battle of Marks' Mill and the Battle of Jenkins' Ferry forcing the Union forces out of southern Arkansas and back to Little Rock.
Until his resignation in 1864 McRae led during battles in northern Arkansas and into Missouri.
After leaving the service, McRae returned to Searcy, Arkansas took up the practice of law. In 1881 he was elected as the deputy secretary of state.
McRae focused his post-war activities on promoting the commercial interests of the State of Arkansas. McRae was a delegate to various commercial expositions and served as president of the bureau of information for Arkansas.
McRae died on 23 April 1899 at Searcy, Arkansas where he is buried.