Captain John F. Johns was a miner, fisherman, and entrepreneur who established a small fishery on Washington Island in 1885, which employed several men (Karamanski 1988:158). Around 1888, Johns acquired nearby Johns Island (formerly known as Johnson Island) and constructed a cottage as an intermittent dwelling and storage facility. While physically removed from the main fishery complex, that cottage played an auxiliary role in its operations. It was inhabited by the Johns family sporadically but was also used by Captain Johns' employees and their families until the 1930s. In poor weather, fishermen could land at Johns island and stay overnight ("Barnum Island: Cultural Landscape Inventory," 2011). Fishermen stored boats in the cabin during the winters, facilitated by a six-foot removable panel cut from the south wall. Captain Johns made a significant contribution to the early tourist industry when he opened Isle Royale's first rustic resort on Barnum Island in 1892, consisting of a hotel and rental cabins. He sold the resort in 1902, but continued to operate his fishery on Barnum Island. As the fishing industry contracted in the 1930s, the auxiliary cabin on Johns Island evolved into more of a private resort camp for the Johns family, even as they continued small-scale fishing operations into the 1950s. In return for the current Johns Island, Edgar R. Johns, Elizabeth Grace Johns, and Robert E. Johns were granted a life lease in 1940. The cottage on Johns Island is the only building associated with the Johns fishery that still stands.
Originally situated closer towards the bay, the small cottage was relocated 20 to 40 meters inland in an attempt by the Johns to gain more land. The usual practice of the National Park Service to draw a north south line at a distance of thirty feet from the back of the structure was known to Edgar Johns. He would have any land from that line towards the cabin to the waters edge east. Mr. Johns rounded up a small group of individuals one afternoon to push and roll the cottage back to its present location. The Johns family successfully gained a few extra feet of land. Edgar R. Johns last visited Isle Royale in the summer of 1958.
On March 24, 1978, Robert Johns wrote to Park Superintendent John Morehead requesting permission to both enlarge and repair the existing cabin. Morehead wrote to Mr. Johns on April 17, 1978, approving his request. The Johns hauled construction materials in from Duluth for the project. Captain Roy Oberg assisted the Johns by transporting these materials from Grand Portage to Johns Island aboard the Voyager II. Oberg reportedly nudged the bow right up on the beach of Johns Island, keeping the stern out in deep water. The Johns ran two 2x4's down onto the dock and began off-loading boards as fast as they could. Tom Johns said that Oberg left the pilot house to watch and a short time later one of the props nicked a rock. Oberg returned to the pilot house warning the men that he was pulling out. The Johns then began throwing the rest of the lumber right into the water and managed to jump off the boat just as the bow cleared the dock.
Instead of a modest enlargement to the existing cabin, the Johns built an entirely new 10' x 15' structure a short distance north of the existing cottage. This adjacent "addition" cabin still stands immediately north of the historic cabin, and the buildings are joined by two plywood walls. The cabin's integrity and historic appearance was slightly impacted by the construction of the adjoining one-room cabin. Overall, Johns Cabin retains a high enough degree of integrity to convey its historic use both as part of a fishery and private resort camp.