Memorial Day was originally known as
"Decoration Day" because it was a time set aside to honor the
nation's Civil War dead by decorating their graves. It was
instituted in 1868 to commemorate the sacrifices of Civil War
soldiers and has since grown to honor all those who have given their
lives in services to their country.
Memorial Day was officially
proclaimed on May 5, 1868 by General John Logan and was first
observed on May 30, 1868, when flowers were placed on the graves of
Union and Confederate soldiers at Arlington National Cemetery. The
first state to officially recognize the holiday was New York in
1873. By 1890 it was recognized by all of the northern states.
(Source: USMemorialDay.com - History of Memorial Day
http://www.usmemorialday.org/backgrnd.html.)