In July 1866, a New York newspaper reported on a "grand gathering" of Union veterans in Salem, Illinois. Gen. John A. Logan, head of the fraternal group the Grand Army of the Republic, made a speech, railing against the defeated Confederates and urging rights and protections for freed slaves.
He also angrily noted that "traitors in the South have their gatherings, day after day, to strew garlands of flowers upon the graves of Rebel soldiers."
He was bothered by reports that in towns across the South, women were decorating the graves of dead Confederates.
Two years later, he proposed the same idea. On May 5, 1868, Logan ordered the first nationwide public holiday on May 30, then known as "Decoration Day," to honor war dead. A national day honoring American men and women who have died while serving in the military has been observed ever since.
Officially, Memorial Day started in Waterloo, New York; that's according to a 1966 law signed by President Lyndon Johnson. And there was definitely a local observance of war dead there in 1866.
But here's the thing - there's no evidence Logan was inspired by or even aware of Waterloo's observance when he pitched his plan.
Contemporaneous coverage doesn't credit Waterloo either. In 1868, the New York Times said: "The ladies of the South instituted this memorial day. They wished to annoy the Yankees; and now the Grand Army of the Republic in retaliation and from no worthier motive, have determined to annoy them by adopting their plan of commemoration."
So if the South had "their gatherings, day after day," as Logan once complained, who in the South started it? The answer to that is complicated; according to the Department of Veterans Affairs, there are more than two dozen cities, mostly in the South, that claim to be the "birthplace of Memorial Day."
There's Macon, Georgia, and Richmond, Virginia. And Columbus, Mississippi, which claims women there decorated the graves of both Union and Confederate soldiers on April 25, 1866, inspiring the poem "The Blue and the Gray," which was published in the Atlantic the next year.
Yale historian David W. Blight has a different theory. African Americans invented Memorial Day, he has lectured, in the spring of 1865 in Charleston, South Carolina, when they reinterred the bodies of Union prisoners-of-war and decorated their graves.
There's no evidence, however, that this commemoration led to others or was more than a one-off event.
More recently, historians have argued that who did it first isn't what's most important; it's who originated the celebrations Logan learned about, was annoyed by and subsequently co-opted.
That's the thesis of a 2014 book "The Genesis of the Memorial Day Holiday in America" by Daniel A. Bellware and Richard Gardiner. They trace it back to a woman named Mary Anne Williams in another city named Columbus - Columbus, Georgia. In March 1866, she sent an open letter to newspapers, saying that women in her area had been cleaning and decorating the graves of "our gallant confederate dead," but that they thought "it is an unfinished work unless a day be set apart annually for its especial attention."
She suggested April 26, the day Confederate Gen. Joseph E. Johnston surrendered the Army of Tennessee near Durham, North Carolina.
The letter was picked up in papers across the South and arrangements were made in a number of towns and cities, Bellware and Gardiner said.
In Columbus, Mississippi, they got the date wrong, celebrating a day earlier - thus its claim of being the birthplace of Memorial Day.
But the honor really belongs to the Columbus in Georgia, Bellware and Gardiner said, because that's where Williams came from, and because it was all of the Confederate grave-decorating across the South that drew Logan's attention and - temporary - disdain.
With this in mind, in 2016, the mayor of Columbus, Georgia, signed a resolution proclaiming that it, too, is the "true" birthplace of Memorial Day.
This article was written by Gillian Brockell, a reporter for The Washington Post.