Three years after the Civil War ended, on May 5, 1868, the head of an
organization of Union veterans — the Grand Army of the Republic (GAR) —
established Decoration Day as a time for the nation to decorate the
graves of the war dead with flowers. Maj. Gen. John A. Logan declared
that Decoration Day should be observed on May 30. It is believed that
date was chosen because flowers would be in bloom all over the country.
The first large observance was held that year at Arlington National Cemetery, across the Potomac River from Washington, D.C.
In 1966, Congress and President Lyndon Johnson declared Waterloo, N.Y., the “birthplace” of Memorial Day.