Half-mast is Eerier Than You Thought
Most people have seen it before, a flag positioned halfway down the pole to represent the passing and mourning of a prominent figure. Whether it be the death of famous person or a brave, local town hero, the gesture is the same. It seems to be a tradition not only locally, but all across the globe. Where did such a uniting symbol originate?
The history of the half-mast tradition dates back to the 17th century. It was then in 1612 that a commander of the ship Heart's Ease was killed at sea. When the ship returned to Britain, the flag on the ship was at half-mast for the mourning of his loss.
One common story is that the flag is not flown at half-mast simply to show respect, but to allow for the invisible flag of death to fly above it. This had lead to the suggestion that flags be positioned one flag's height from the top instead, though half-mast seems to be the most prevalent location.
Another theory
There is an alternate theory of origin which says that the flag flown at half-mast was part of a bigger concept of making ones ship look messy and out of shape if a crew member were to die; this could also include setting the sails poorly or leaving slack in ropes that should usually be taught. People would expect a ship to be very clean and organized, and so the untidiness would be said to represent mourning.