Early French historical documents begin to mention the Atikamekw at the beginning of the 17th century when they lived in the boreal forest of the upper Mauricie. In these early documents, the French colonists recorded the Atikamekw as "Atikamegouékhi" to transliterate their name for themselves. The Atikamekw were described as a group of 500 to 600 people who made up "one of the nations more considerable of the north."
For food, they fished, hunted, and trapped. They supplemented their diet with agricultural products made and processed by women, such as corn and maple syrup. The latter was boiled to reduce as a syrup after sap was tapped from maple trees. Both men and women made tools from wood and animal parts, such as bone and tendon. The women made clothing from tanned animal hides. Tribal members traded with other native peoples in nearby areas, but trading networks connected along long distances. In summer, the Atikamekw would gather at places like Wemotaci. In the fall, they would pack for the winter season and disperse into smaller encampments through the boreal forest.
After the French entered the trading network, they introduced new, European manufactured goods, such as metal tools. The Atikamekw traded furs for such goods, becoming increasingly dependent on European goods in the fur trade. They were described as peaceful, sharing the region with the Innu (Montagnais) in the east, the Cree in the north, and the Algonquin to the south. The Mohawk of the Iroquois Confederacy, whose five nations were based south of the Great Lakes, competed with them for the lucrative beaver trade and over hunting grounds. Through their Innu allies, the Atikamekw caught new infectious diseases that were endemic among the Europeans. Around 1670-1680, a smallpox epidemic devastated the Atikamekw tribe.
The French pulled the Atikamekw into a trade war between the Montagnais (Innu) and the Mohawk, in which the Atikamekw and Innu did not fare well. The more powerful Mohawk killed many Atikamekw who had survived the smallpox.
However, at the start of the 18th century, a group called "Tête-de-Boule" by the French reappeared in the region. While there exists no certainty as to the origin of this group, they may have been a regrouping of the few Atikamekw survivors who were possibly associated with other indigenous nomadic tribes. But they are considered unrelated to the former Atikamekw even though they lived in the same area and took on the same name.
Today, the Atikamekw, like their historical allies, the Innu, have suffered from mercury poisoning due to contamination of their water supply by the operations of the central electric power companies before much environmental regulation.