Porte des Morts, also known as Porte des Mortes, the Door of Death, and Death's Door is a strait linking Lake Michigan and Green Bay between the northern tip of the peninsula of Door County, Wisconsin and a group of islands historically known as the Potawatomi Islands and dominated by Washington Island. The name is French and means, literally, "the door of the dead".
North of the peninsula, warm water from Green Bay flows into Lake Michigan on the surface, while at the same time, cold lakewater enters Green Bay deep underneath.
According to traditions given by the Native Americans to area fishermen in the 1840s and reported both by Captain Brink, a government engineer who surveyed the area in 1834, and by Hjalmar R. Holand in his two-volume history of Door County, the ominous name is traced back to a battle between the Winnebago and Potawatomi tribes. Various historical accounts indicate that it was the Potawatomi who were the newcomers to the area and that the Winnebago had recently suffered greatly at the hands of the Illinois. If this account accurately gives the origin of the name, the battle probably occurred in the mid seventeenth century, shortly after the Potawatomi settled in the area and before the French used the area enough to name the strait.
Other explanations for the origin of the name have been offered. It has also been said that the French, not wanting the English to establish fur trade routes to Wisconsin and other surrounding areas, named the passage to discourage and scare sailors from sailing through the strait. Yet the strait had its name well before the English were coming to the Great Lakes.
It is possible that the "doorway to death" name has a much larger significance. The written history of the area between Jean Nicolet's visit to Green Bay in 1634 and the return of French trappers in the late 1650s is virtually a blank page. Thus, the only reasons that can be found for the drastic reduction in the population of the Winnebago in that time period—from estimates of between ten and twenty thousand to five, six, or seven hundred—are those that can be gleaned from the natives' own oral traditions, which by the time they make it to a recorder's pen often mix and confuse details of separate events. David Edmunds relates that after the Winnebago successfully repulsed the first advance of the Potawatomi, they lost several hundred warriors in a storm on Lake Michigan.
