|Location||Mouth of the St. Clair River at Lake St. Clair|
|County||St. Clair County|
The Island was named for its first white settler, James (or Jacob) Harsen, a Dutchman, who came from New York state in about 1779 with his son-in-law Isaac Graveraet (or Graveret). Harsen bought the island from the Indians in 1783. It was also known as "Jacob Island" (also James or Jacobus Island) as late as 1809. The name of the post office, Sans Souci, was changed to "Harsens Island" in 1960.
The nation "owning" the island was a disputed matter for many years. The 1783 Treaty of Paris that ended the American Revolutionary War described the international boundary line with imprecise terms in several places, including the mouth of the St. Clair River. The area had not been surveyed at that time. In the most commonly known map of the area from that period, made by John Mitchell in 1755 and which was used in negotiating the treaty, the delta and all the islands at the mouth of the St. Clair River are absent. In the language of the treaty, the boundary line was to run through the middle of Lake Erie until it arrives at the water communication between that lake and Lake Huron, "thence along the middle of said water communication into the Lake Huron". Due to this vagueness, all of the delta islands, including Harsens and Dickinson, were claimed by the British, and some from the United States who did not want to give up their English citizenship following the war made their residences there. The area was administered by the Hesse District of Upper Canada, including the awarding of land grants. In 1809, surveyors for the British government placed the boundary line in the north channel, which placed all of the delta and islands under British control.
However, in the 1814 Treaty of Ghent, which ended the War of 1812, the ambiguity of provisions in the 1783 were acknowledged: "And, whereas, doubts have arisen, what was the middle of the said river, lakes, and water communication, and whether certain islands lying in the same were within the dominions of his Britanic majesty, or of the United States." To decide these questions, two commissioners were to be appointed, one from each nation, to designate the international boundary. They executed their survey of the Detroit River, Lake St. Clair, and the St. Clair River in 1819 and 1820 and issued their final conclusions on June 18, 1822. Their decision regarding the St. Clair River delta was that the boundary should run north through Lake St. Clair, entering "that mouth or channel of the River St. Clair which is usually denominated the Old Ship Channel; thence along the middle of said channel, between Squirrel Island on the southeast, and Herson's [sic] Island on the northwest, to the upper end of the last mentioned island, which is nearly opposite to Point aux Chenes, on the American shore; thence along the middle of the River St. Clair, keeping to the west of, and near, the islands called Belle Riviere Isle, and Isle aux Cerfs, to Lake Huron." By this conclusion, both Harsens and Dickinson Islands were placed on the U.S. side of the boundary.
To further exemplify the somewhat loose awarding of the area in question, arose in 1870 involving Hiram Little of Wallaceburg a Captain who was given a contract to provide cord wood and supplies to a work crew. At the time, a ship canal was being dredged through the marshy areas near Lake St. Clair. By this time shipping was increasing and the need for a deep, free flowing canal was required. During one trip to the work area, Capt. Little's ship was seized by U.S. officials who claimed he was operating illegally since he was in U.S. waters. Little protested claiming he was in Canadian water, challenging U.S. officials to prove their contention. After searching of documents, including contact with Crown in England who supplied early charts, Capt. Little was ultimately proven correct. To avoid further embarrassement, the U.S. officials simply moved the international boundary east further infriging on Canadian (and native) land. The present St. Clair River from Russel Island to Lake St. Clair has been the International boundary line between Canada and the United States ever since, although who legally should own Harsen's Island and the St. Clair delta area remains speculative in some eyes.
The St. Clair River is an integral part of the Great Lakes, draining water from Lake Huron down, eventually, to Lake Erie. The river is the international boundary between the United States and Canada. The river carries more freighter traffic than the Suez and Panama Canals combined. Over 1 billion US gallons (3,800,000 m3) of fresh water per day flow down the St. Clair River, and through its delta region, the St. Clair Flats. Harsens Island is the major U.S. island in the Flats. The Canadian side of the Flats has the largest islands in the delta including Walpole Island, home to the Walpole Island First Nation of Native Americans. The St. Clair Flats is home to wildlife such as the great blue heron, snapping turtles,watersnakes, muskrats, mink, whitetail deer, pintail, canvasback and mallard ducks, Canada geese and red-winged blackbirds. The area is a popular fishing spot with yellow perch, large and small mouth bass, rock bass, carp, sunfish, pumpkinseed fish, bluegills, and silver bass available. The State of Michigan owns about 75% of the area of the Island, and has waterfowl and wildlife sanctuaries throughout.
Harsens Island is the only U.S. island in the Flats that can be reached by automobile ferry, and the only one with roads, an unincorporated community, Sans Souci, a school (now closed, and has subsequently re-opened as the "Harsens Island Schoolhouse Grille"), and a small airport. All the other U.S. islands—there are scores of them—are accessible only by boat.
- Romig, Walter. Michigan Place Names. Detroit: Wayne State University Press, 1986.
- Jenks, William Lee. St. Clair County, Michigan, its history and its people. Chicago and New York: The Lewis publishing company, 1912.
- Bkejwanong Walpole Island First Nation website @ http://www-personal.umich.edu/~ksands/Warpole.html
- Aerial views of Harsens Island http://www.aerialpics.com/H/harsensisland.html
- Harsens Island News News & events from all around Lake St. Clair
- Harsens Island Home Page Harsens Island.com - Your Source For Information