Back when Karate was still known as Chinese hands or "Te." there was no need for
a Belt grading system. Everyone in the Dojo knew who the senior student and
Teacher or Master was.
In the early days of Okinawan Martial Arts, all Karate do practitioners started
out with a White Belt. In time, and the change of seasons, spring would come
about and with it green grass, pollen and dust. Since the Belt was never washed
as a symbol of hard work put forth into ones training as it is today, spring
could leave behind on your white belt a tinge of green since most Dojo’s of the
day were exposed to the outdoor elements.
Depending on how much training you participated in, the coming of fall and
winter would bring about different pigments in the air that would further stain
the once white belt. After the several turning of seasons, and the repeated
summer’s heat that baked and darkened the colours, the belt eventually turned
black.