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Beaver Wars

Beginning in 1609, the League engaged in the decades-long Beaver Wars against the French, their Huron allies, and other neighboring tribes, including the Petun, Erie, and Susquehannock. Trying to control access to game for the lucrative fur trade, they invaded the Algonquian peoples of the Atlantic coast (the Lenape, or Delaware), the Anishinaabe of the boreal Canadian Shield region, and not infrequently the English colonies as well. During the Beaver Wars, they were said to have defeated and assimilated the Huron (1649), Petun (1650), the Neutral Nation (1651), Erie Tribe (1657), and Susquehannock (1680). The traditional view is that these wars were a way to control the lucrative fur trade to purchase European goods on which they had become dependent. Starna questions this view.

Recent scholarship has elaborated on this view, arguing that the Beaver Wars were an escalation of the Iroquoian tradition of "Mourning Wars". This view suggests that the Iroquois launched large-scale attacks against neighboring tribes to avenge or replace the many dead from battles and smallpox epidemics.

In 1628, the Mohawk defeated the Mahican to gain a monopoly in the fur trade with the Dutch at Fort Orange (present-day Albany), New Netherland. The Mohawk would not allow northern native peoples to trade with the Dutch. By 1640, there were almost no beavers left on their lands, reducing the Iroquois to middlemen in the fur trade between Indian peoples to the west and north, and Europeans eager for the valuable thick beaver pelts. In 1645, a tentative peace was forged between the Iroquois and the Huron, Algonquin, and French.

In 1646, Jesuit missionaries at Sainte-Marie among the Hurons went as envoys to the Mohawk lands to protect the precarious peace. Mohawk attitudes toward the peace soured while the Jesuits were traveling, and their warriors attacked the party en route. The missionaries were taken to Ossernenon village, Kanienkeh (Mohawk Nation) (near present-day Auriesville, New York), where the moderate Turtle and Wolf clans recommended setting them free, but angry members of the Bear clan killed Jean de Lalande and Isaac Jogues on October 18, 1646. The Catholic Church has commemorated the two French priests and Jesuit lay brother René Goupil (killed September 29, 1642) as among the eight North American Martyrs.

In 1649 during the Beaver Wars, the Iroquois used recently-purchased Dutch guns to attack the Huron, allies of the French. These attacks, primarily against the Huron towns of Taenhatentaron (St. Ignace) and St. Louis in what is now Simcoe County, Ontario, were the final battles that effectively destroyed the Huron Confederacy. The Jesuit missions in Huronia on the shores of Georgian Bay were abandoned in the face of the Iroquois attacks, with the Jesuits leading the surviving Hurons east towards the French settlements on the St. Lawrence. The Jesuit Relations expressed some amazement that the Five Nations had been able to dominate the area "for five hundred leagues around, although their numbers are very small". From 1651 to 1652, the Iroquois attacked the Susquehannock, to their south in present-day Pennsylvania, without sustained success.

In 1653 the Onondaga Nation extended a peace invitation to New France. An expedition of Jesuits, led by Simon Le Moyne, established Sainte Marie de Ganentaa in 1656 in their territory. They were forced to abandon the mission by 1658 as hostilities resumed, possibly because of the sudden death of 500 native people from an epidemic of smallpox, a European infectious disease to which they had no immunity.

From 1658 to 1663, the Iroquois were at war with the Susquehannock and their Lenape and Province of Maryland allies. In 1663, a large Iroquois invasion force was defeated at the Susquehannock main fort. In 1663, the Iroquois were at war with the Sokoki tribe of the upper Connecticut River. Smallpox struck again, and through the effects of disease, famine, and war, the Iroquois were under threat of extinction. In 1664, an Oneida party struck at allies of the Susquehannock on Chesapeake Bay.

In 1665, three of the Five Nations made peace with the French. The following year, the Governor-General of New France, the Marquis de Tracy, sent the Carignan regiment to confront the Mohawk and Oneida. The Mohawk avoided battle, but the French burned their villages, which they referred to as "castles", and their crops. In 1667, the remaining two Iroquois Nations signed a peace treaty with the French and agreed to allow missionaries to visit their villages. The French Jesuit missionaries were known as the "black-robes" to the Iroquois, who began to urge that Catholic converts should relocate to the Caughnawaga, Kanienkeh outside of Montreal. This treaty lasted for 17 years.