Starting in the 1600s, multiple outsider groups arrived in Michigan, leading to significant changes in the lives of the Natives living there. The French were the first Europeans to travel to the western Great Lakes region, arriving in small numbers as explorers, missionaries, and traders. As early as 1620, young Frenchman Etienne Brûlé, who had been sent by Champlain to live with the Huron people to learn their language and customs, traveled with a group of Huron to the shore of Lake Superior. Jean Nicollet canoed through Lake Michigan to its western shore in 1634, encountering members of the Winnebago (Ho-Chunk) tribe. And in 1641, Ojibwe Natives escorted two Jesuit priests, Father Charles Raymbault and Father Isaac Jogues, to Sault Ste. Marie after inviting the two missionaries to accompany them to their homeland.

After these early encounters between French and Native people, the French established settlements primarily in three areas of what is today Michigan: at the Straits of Mackinac, in the St. Joseph River valley in southwest Michigan, and at Detroit in southeast Michigan. Several motivations drove the French to explore and settle here, in an area they called le pays d’en haut or the Upper Country, as it lay upstream from their early colonies of Quebec, Montreal, and Trois-Rivières along the St. Lawrence River.

First, they wished to find a westward passage to the Pacific Ocean and thus to Asia; next, they wanted to expand the fur trade and its economic benefits for France; and finally, they sought to establish political alliances with the Native peoples in order to contain the British colonists and their Iroquoian Native allies along the east coast of North America. In addition, the Catholic Church and in particular Jesuit missionaries were eager to convert Native Americans to Catholicism. For all these reasons, the French settlements were sited on waterways in order to have good access for travel and trade, they were nearly always in close proximity to Native villages, and were often paired with church missionary sites.

In 1688 Father Jacques Marquette established the first European permanent settlement in northern Michigan at Sault Ste. Marie among refugee Huron, Petun (Tionontate) and Odawa groups. Farther south, at the Straits of Mackinac, the mission of St. Ignace was established in 1671, first on the island then called Michilimackinac and soon after on the north side of the Straits. Soon after, the French established Fort de Buade close to the Huron and Odawa settlements just south of the mission of St. Ignace, in large part to stop the intrusion of the British into the fur trade, as they wished to have exclusive control over the trade in this region. However, though Fort de Buade was the center of French military activity for over ten years, soon there was an oversupply of furs being traded to the French, and they closed the fort and trading post in 1697, burning the mission in 1705.

The Straits nonetheless remained an important meeting place for the Native peoples and the French. The Odawa continued to cultivate agricultural fields near the Straits, one of several sites among which they moved as they rotated their cultivated plots. The French built a new fort on the south side of the Straits in 1715. Its name was Fort St. Philippe, but it was generally called Michilimackinac. Priests from St. Ignace built a chapel here, and troops were stationed here so that the French could exercise some control over the fur trade and attempt to create and maintain alliances with various Native groups. It became an important rendezvous point for the fur trade, and a place where the French tried to maintain and develop their relations with the Odawa and Ojibwe people who called this area their home. The site of the fort began to be investigated by archaeologists in 1959, and their work is ongoing.

Fort Pontchartrain, located on the north bank of the Detroit River between Lake Erie and Lake Huron, was the first French settlement in southeast Michigan. Founded in 1701 and directed by Antoine de la Mothe Cadillac, the outpost quickly developed into one of the most important military and commercial posts in the pays d’en haut because of its strategic location on the river connecting two of the Great Lakes, now known as Lakes Erie and Huron. French settlers constructed the fort and the houses within it along the riverfront in what is now downtown Detroit. Soon after its establishment, groups of Huron (Wyandot), Odawa, and Potawatomi formed villages nearby. The fort and growing town—it was enlarged sometime after 1749, doubling its size—became a multi-ethnic settlement during the first decades of the eighteenth century, one which was politically and economically beneficial to both Natives and French.

The third major area of French presence in what is today Michigan was in the lower St. Joseph River valley. René-Robert Cavelier, sieur de La Salle, made an attempt in 1679 to establish a usable port by establishing Fort Miami at the mouth of the St. Joseph River, but this fort was abandoned by 1682. In 1691, however, Augustin Legardeur de Courtemanche, along with a dozen soldiers, was sent to build a fort on the St. Joseph River, then known as the River of the Miamis. Its location, near Lake Michigan, the Sauk Trail (connecting present-day Detroit and Chicago) and the Mississippi drainage, meant that it, like the other French forts, provided access to crucial routes for trade and the movement of both Native Americans and Europeans.

Native presence in the valley was substantial, though it changed over time. In the late 1600s both Miami and Potawatomi people moved to the area, coming from areas where they had taken refuge earlier in the century. There were at least 2,000 Native people there in the 1700s, greatly outnumbering the French population at the time. The small fort, which was in existence for nearly a century, probably housed some three dozen or so European inhabitants at any one time—soldiers, a blacksmith, an interpreter, a priest, and traders with their families. The site of the small fort in present-day Niles has been the subject of archaeological investigation since 1998, with ongoing research aimed at studying the fur trade and the colonial presence in southwest Michigan.