Did African Americans invent Memorial Day?

The first widely-publicized observance of a Memorial Day-type observance after the Civil  War was in Charleston, South Carolina, on May 1, 1865

[h/t Wikipedia].

The first widely-publicized observance of a Memorial Day-type observance after the Civil War was in Charleston, South Carolina, on May 1, 1865. During the war, Union soldiers who were prisoners of war had been held at the Hampton Park Race Course in Charleston; at least 257 Union prisoners died there and were hastily buried in unmarked  graves.^[13]

Together with teachers and missionaries, black residents of Charleston organized a May Day ceremony in 1865, which was covered by the New York Tribune and other national papers. The freedmen cleaned up and landscaped the burial ground, building an enclosure and an arch labeled "Martyrs of the Race Course." Nearly 10,000 people, mostly freedmen, gathered on May 1 to commemorate the war dead. Involved were about 3,000 school children, newly enrolled in freedmen's schools, as well as mutual aid societies, Union troops, black ministers and white northern missionaries. Most brought flowers to lay on the burial field. Today the site is remembrance celebration would come to be called the "First Decoration Day" in the North.

David W. Blight described the day:

This was the first Memorial Day. African Americans invented Memorial Day in Charleston, South Carolina. What you have there is black Americans recently freed from slavery announcing to the world with their flowers, their feet, and their songs what the war had been about. What they basically were creating was the Independence Day of a Second American Revolution.^[14]

However, Blight stated he "has no evidence" that this event in Charleston inspired the establishment of Memorial Day across the country.^[15]

On May 26, 1966, President Johnson signed a presidential proclamation naming Waterloo, New York, as the birthplace of Memorial Day. Earlier, the 89th Congress had adopted House Concurrent Resolution 587, which officially recognized that the patriotic tradition of observing Memorial Day began one hundred years prior in Waterloo, New York.^[16] Other communities claiming to be the birthplace of Memorial Day include Boalsburg, Pennsylvania, Carbondale, Illinois, Columbus, Georgia, and Columbus, Mississippi.^[17] A recent study investigating the Waterloo claim as well as dozens of other origination theories concludes that nearly all of them are apocryphal legends.