Plum Island is located off of the tip of Door County, midway between the mainland and Washington Island, on the Porte des Morts passage. The 325 acre island was reserved from the public domain in 1848 for lighthouse purposes.

The first lighthouse on the island, together with a keeper's dwelling, was completed in 1849. However, navigation of the passage continued to the difficult. The majority of the current resources on the island date to 1896 after Congress authorized additional funds for Plum Island. These include the life-saving station, the keepers' dwelling, the rear range light, and the fog signal building. A major addition to the island’s function came in 1939 with the construction of a large boathouse and the expansion of the pier and breakwater. This was the same year that the Coast Guard took over all lighthouse operations.

While the lighthouse provided guidance to ships, the life-saving station located on the island's east side assisted stranded or damaged vessels. The lights on the Island were operated seasonally, typically from April through December. During the off months, the keepers and their families would return to the mainland or to nearby Washington Island.

The Coast Guard operated the station and acted as the "Guardians of Death's Door" until 1990. In 2007, the island was transferred the US Fish and Wildlife Service.