These days we honour the dead from war on 11th November, however it isn't the only date, in America the dead of the Civil War memorial day is celebrated on the last Monday in May, and is no longer a fixed date, this was changed in 1971.
The Official date of Memorial day was observed on 5th May 1866, however General John Logan was impressed how the South respected their dead after the Civil War and led a call for a National Holiday for all the Dead.
Logan while in the Capital H.Q. chose 30th May 1868 and then on Memorial Day that was eventually changed in 1971.
He used sunset for alignment, being ancient Greek day start that happened at 19:12:28pm on 29th May 1868, the west was always associated with death with the ancient Egyptians being where the Sun Died at the end of the day!
Memorial Day - Wikipedia, the free encyclopedia