supposedly from the sport of cock fighting, with the belief that cockerel’s [sic] sporting these white feathers were poor fighters
This propaganda campaign and method of shaming began in 1914 when the Order of the White Feather was started by Admiral Charles Fitzgerald and used women to shame men into enlisting as, at the time, there was no conscription. In what became a controversial campaign, women gave men who they thought hadn’t enlisted a white feather as a mark of shame or cowardice for failing to perform their duty. One problem was that some recipients were in reserved occupations while, in one case, a man received such a feather on the same day as the Victoria Cross.
The inspiration for this campaign seems to have come from the novel The Four Feathers published in 1902 and set in the late 19th century but, according to both Wikipedia and this article The Order of the White Feather, the tradition dates back to the 18th century. However, neither source gives any further details.
Are there any recorded incidences of white feathers being used in this way in the 18th century?
If not, when is the first recorded incidence of someone being given a white feather?