The mourning cloak butterflies are distributed broadly around the northern hemisphere. Three subspecies of mourning cloak butterflies are found throughout North America: northern
Nymphalis antiopa hyperborea Seitz, 1913; eastern
N. a. lintnerii Fitch, 1857; southwestern
N. a. thomsoni Butler, 1887. They can usually be found in hardwood forests, though they have been found in virtually all habitats. They may also be found as far as the northern part of South America, though they are typically not seen as frequently in southern states such as Florida, Louisiana, or Texas. They are occasionally seen in the more temperate places in Asia, and a few have even been seen in Japan. However, the mourning cloaks tend to be found predominantly in cold, mountainous areas. Migrants arrive in
Great Britain most years during summer and autumn, but numbers are usually very low. There is no evidence that the species breeds in Britain; it is thought that mild, wet winters prevent them from surviving there for very long. The 'Butterfly Farmer'
L. Hugh Newman raised thousands for release at his 'farm' in
Bexley, but none were seen the following spring. Specimens stored in his refrigerator for the winter, however, survived. In a book he said that Camberwell Beauty catches in England were suspiciously concentrated around London,
Hull and
Harwich, all these being ports in the timber trade with
Scandinavia, and theorized that they had hibernated in stacks of timber which was then shipped to England, and had not traveled naturally. ==Morphology ==