General John A. Logan issued the order that launched the first national Decoration Day observance on May 5, 1868.
Logan was commander-in-chief of the Grand Army of the Republic, a major organization of Union veterans. His General Order No. 11 called on members to decorate the graves of Civil War dead with flowers on May 30, 1868.
The order helped turn local grave-decoration customs into a coordinated national observance. The first national event took place at Arlington National Cemetery, where participants honored Union soldiers buried there.
May 30 remained the traditional date for decades. In 1971, federal law moved Memorial Day to the last Monday in May, creating a three-day weekend. The original 1868 order is therefore important because it established the national observance, not because it created the modern federal holiday calendar.