This miniature had previously been classified as European, but a kind expert has advised it is more likely to be British.
The sitter and artist are unknown. Based upon a comparison with wig examples shown in Corson, "Fashions in Hair" this appears most similar to one in Plate 68 (I) which is described as a "long bob", but "sometimes called a miniater's or clergyman's bob" and dates from around 1735.
However, this type was probably in use for many years from that date. 794