THE ISSUE In 1868, three years after the Civil War ended, the leader of an organization of Union veterans established Decoration Day â as Memorial Day originally was known â as a time for the nation to decorate the graves of the war dead with flowers. According to Utahâs Deseret News, one of the very first Memorial Day celebrations may have been even earlier, on May 1, 1865, when Black workmen gathered at a Charleston, South Carolina, racecourse and club that the Confederates had converted into an outdoor prison. That newspaper cited Yale University historian David W. Blight, who said the men reinterred the bodies of Union prisoners of war buried there and decorated their graves; later that day, a parade led by 3,000 Black schoolchildren carrying armloads of roses was held. In 1971, Congress established that Memorial Day would be observed as a national holiday on the last Monday in May.