The expedition of French explorer René Robert Cavelier, Sieur de La Salle entered the lake on August 12, 1679, the feast day of Saint Clare of Assisi, and named it Lac Sainte-Claire in her honor.

[5] On English maps as early as 1710, the lake is labelled as Saint Clare (the latter the French spelling).

[6] The name is sometimes attributed to honoring the American Revolutionary War General Arthur St. Clair, who was President of the United States in Continental Congress during the drafting of the United States Constitution, and Governor of the Northwest Territory, but the name was in use with the current spelling long before St. Clair was a notable figure.

Pontiac's Rebellion had taken place the year before and the British wanted a military base on the St. Clair River to protect their shipping route between Detroit and Fort Michilimackinac.

In 1817, Robert Fulton platted a town on the north side of the Pine River.

The sawmill industry began to flourish due to the area's large supply of pine and oak.

Clay from the Pine River's banks provided the material for several brickyards that operated into the Twentieth Century.

Many of the town's men became sailors on the Great Lakes and numerous captains built homes in the city.

In addition to the natural wonders of the area, both hotels offered mineral baths.

The crown jewel of the project was the expansion of Palmer Park with its boardwalk along the St. Clair River.

[citation needed] As of the census[10] of 2010, there were 5,485 people, 2,306 households, and 1,521 families residing in the city.