This tradition goes back to the sixteenth century and arose out of a signal of surrender when the losing ship in a battle would lower their flag halfway down the mast acknowledging submission.
When the ships entered a port, the flags remained in that position in recognition of the brave individuals who had lost their lives at sea.
In the seventeenth century this tradition was extended in honor of combatants who had made the supreme sacrifice in land battles serving their country beyond the call of duty.
Today the honorable recognition applies to all deceased participants on land, at sea or in the air.
The lowering of the flag is the prelude to further burial ceremonies honoring the men and women of all races and creeds, who have made the Supreme Sacrifice in defense of America.
(Excerpts from “The Little Book of Answers” – Author – Doug Lennox – (2003) – MJF Books – New York, NY 1001.)