Henry James Snow hunted marine mammals in the sub-Arctic Kuril Islands and adjacent areas of the North Pacific between the years 1873 and 1896. His success resulted from careful study of the animals hunted, in particular the sea otter. He had continual difficulties with the governments of Japan and Russia, which had sovereignty over the land and territorial waters of the region, some of the encounters involving violence. At the same time, Snow was a careful observer of the wildlife and surveyor of the natural features, especially of the Kuril Islands. His works represented the most accessible source of information about the islands as late as the start of the Pacific War in 1941.