The French and Algonquin started pushing the Iroquois back to New York In 1687. The Algonquin people group consists of those who speak Algonquian languages (Potawatomi is classified as a Central Algonquian language).

As the invaders withdrew, the Potawatomi began migrating south along Lake Michigan, reaching its southern tip by 1695.  One band settled near the Jesuit mission on the St. Joseph River in southwest Michigan.

In 1701, the French built Fort Pontchartrain at Detroit, where groups of Potawatomi would soon settle nearby.

References:

Potawatomi. (2018, October 25). New World Encyclopedia. Retrieved 14:38, April 23, 2019 from http://www.newworldencyclopedia.org/p/index.php?title=Potawatomi&oldid=1015500.