According to Wikipedia, "The word Anglican originates in ecclesia anglicana, a medieval Latin phrase dating to at least 1246 that means the English Church." However, this usage referred to the Catholic Church in England.
Although the use of the word 'Anglican' "did not become general until the latter half of the 19th century", it was used in the context of the Protestant Church of England long before this.
The online dictionary.com says 1625-35 while Merriam-Webster gives the earlier date of 1598. Wikipedia is less specific, saying the 16th century. However, none of these sources say where or who first used it. I've looked at several religious sites but have found no mention of first usage. In fact, these sites use the word 'Anglican' as if it had been in use since the founding of the Protestant Church of England (see, for example, here and here).
Is the Merriam-Webster date of 1598 the first documented use? If so, where was it used, or who used it? If not, what is the first documented use?