On this day in 1868, the first Decoration Day was observed, the predecessor to our modern Memorial Day. General John A. Logan issued the proclamation calling for a "Decoration Day," to be observed annually and nationwide, to commemorate the Union and Confederate soldiers who died fighting in the Civil War.
He chose May 30 because the date was not the anniversary of any particular battle, and it was an optimal time for flowers to be in bloom.
It wasn't until 1968, and the Uniform Monday Holiday Act, that Memorial Day was changed to the last Monday in May.
Speaking at Arlington Cemetary on Decoration Day in 1880, Representative George C. Hazelton from Wisconsin spoke about some of the underlying causes of the War.
"The conflict of arms in which over a quarter of a million* American freeman lost their manly lives, and which you of the Grand Army of the National Republic happily survive, was the natural and irresistible result--the culmination in war of a long civil conflict over principles which underlie free government, and which constitute the very foundations of civilizations and human progress...
The issue between the two forces closely drawn and well defined, compassed the territorial integrity of the government; the destruction of the union and of liberty itself. The one sprung to arm upon the abstraction that the right of succession was reserved to the States and upon the theory that by right, capital should own its labor, control it, buy it, sell it, debauch it.
The other came to the fields of war with the conviction entrenched within its heart that the Union was inseparable, that labor should be its own master, wear no shackles, and stand erect before the law of government, and before God and man, honorable, and honored.
Liberty, then, must cast her fortune with the Union cause or perish on our continent."
*Later estimates brought this total to 620,000, and some experts argue the total is more like 750,00.
The entire Decoration Day oration from Hon. George C. Hazelton
Wikipedia entry on the Uniform Monday Holiday Act
Wikipedia entry on George C. Hazelton
Civil War Trust
Historian revises estimate of Civil War dead