Fort de Buade

During the 1690s, the fort became a staging area for French and Indian attacks against the Seneca, who were then allied to the English. It remained an important fur trading center and a distribution point for arms and munitions for the war against the Iroquois. In 1694 Governor Louis de Buade de Frontenac sent an aggressive young protégé, Antoine de la Mothe Cadillac, to run the post. Cadillac made a small fortune as the post commander, possibly by collecting bribes. In 1697, the Huron chief Kondiaronk from Michilimackinac led an attack on the Seneca at Lake Erie. He gained a crushing victory and dashed the Seneca hopes for victory against the French. Four years later, Kondiaronk took a leading role in forging the Great Peace of Montreal, which would conclude the war.

Relations between the fort and the adjacent Jesuit mission were not good during Cadillac's tenure. La Durantaye had ruled Michilimackinac with a firm hand. He controlled the trade in brandy, policed the fur trade, and kept the traders in line. An honest man, he would spend the last years of his life in relative poverty. Cadillac did not hold to these standards. He brought in for sale much of the alcohol at the post. The missionaries, led by Etienne de Carheil, accused Cadillac of encouraging the sale and trading of brandy to the Native Americans. Cadillac may have seen this move as a necessary tactic to check the English traders. In any case, he used it as a tactic in his own financial plans.

Despite Cadillac's liquor trade, Anglo-French commercial competition continued. Cadillac was replaced as commandant by Alphonse Tonti, brother of the explorer Henri de Tonti. In 1701, Cadillac asked permission from Paris to found a new post on the Detroit River, to interdict the flow of British trade goods into the Lake Huron area. In that sense, the Fort de Buade garrison was related to development of the future city of Detroit.

The final fate of Fort de Buade is unclear. After the withdrawal of the garrison, coureurs de bois continued to frequent Michilimackinac. Governor Philippe de Rigaud Vaudreuil used these traders to smuggle goods to the northern nations during the War of the Spanish Succession, despite the objections of Jérôme Phélypeaux, comte de Pontchartrain. Among his agents was the voyageur Daniel Amiot de Villeneuve. Unless the fort was destroyed when the garrison was evacuated, Vaudreuil's men likely used it to store goods intended for the Indians, until the new fort was completed on the south side of the Straits (1715). After this date few French remained at East Moran Bay. The fort was either destroyed or fell into disrepair and eventually disappeared.

The 1690-1701 Fort de Buade was probably built as a wooden stockade. It is believed to have been located on a site within the current municipality of St. Ignace, possibly on a hill above East Moran Bay locally called "Fort Hill." The fort could also have been located on the bay's waterfront. As of May 2017 the fort's remains had not yet been found.

Between 1701 and 1715 there was no official French-Canadian presence at the Straits of Mackinac. Unlicensed fur trading by coureurs des bois no doubt continued during this period. In 1715 a French detachment under Constant le Marchand de Lignery re-established a presence at the Straits of Mackinac to prepare for war against the Fox nation in Wisconsin (Fox Wars). The new post, called Fort Michilimackinac, was built on the south shore of the Straits. Present-day Mackinaw City, Michigan developed near it. Most of the Huron migrated south to Detroit with Cadillac in 1701. The Ottawa moved from East Moran Bay to the new fort, and the St. Ignace area was largely abandoned until the nineteenth century.