Memorial Day was initially called Decoration Day, according to the U.S. Department of Veteran Affairs. The holiday was born of a wish to honor those who died during the Civil War.
It is believed that May was chosen because it was a time when flowers would be in bloom.
Various cities in both the North and the South claim to be the birthplace of Decoration Day, having honored the dead shortly after the war.
Congress named Waterloo, N.Y., the official birthplace of the holiday. A citywide, formal observance was first held there on May 5, 1866.
The first large observance of Decoration Day took place at the Arlington National Cemetery in May 1868. During that ceremony, children placed flowers at the graves of both Union and Confederate soldiers, singing hymns and reciting prayers.
Cities all around the country were observing the holiday by the end of the 1800s.
Initially celebrated on May 30, the holiday was shifted to the last Monday of the month in 1971.
1971 was also the year that the holiday was expanded to honor those who had died in all wars, and Congress declared Memorial Day an official national holiday.