When Étienne Brûlé in 1610 and Samuel de Champlain in 1613 became the first Europeans to travel up the Ottawa River, they were assisted by Algonquin guides. Written records show that by 1613 the Algonquins were in control of the Ottawa Valley and the surrounding areas to the west and north. These original inhabitants of both sides of the Ottawa River possibly had lived along its banks for several thousand years. This First Nations call themselves Anishinaabe. There is confusion regarding the Ottawa people, another First Nations people who live far to the west along Georgian Bay and Lake Huron, but they have never lived in the area, having only used the Ottawa River for only several years as a trade route.
Brûlé and Champlain were travelling west to the Great Lakes, but it would be awhile before the Europeans showed much interest in the area. However Brûlé encountered the Chaudière Falls, and the future site of what would be the City of Ottawa. The Chaudière Falls would serve as power for the lumber industry which stimulated the early growth of settlement in the area. Champlain himself originated the name, chaudière, as he describes in his journal on June 14, 1613,
At one place the water falls with such violence upon a rock, that, in the course of time, there has been hollowed out in it a wide and deep basin, so that the water flows round and round there and makes, in the middle, great whirlpools. Hence, the savages call it Asticou, which means kettle. This waterfall makes such a noise that it can be heard for more than two leagues off.
The English would later refer to the falls as the "Big Kettle".
The area includes Chaudière Island and Victoria Island to the east of that, and according to archaeological evidence, had been used by First Nations people for centuries as a centre of convergence for trade and spiritual and cultural exchange. Later the nearby Parliament of Canada would speak of Ottawa as "a meeting place of three rivers, perched on a rocky point overlooking fast-moving water, wooded land and urban landscapes, within sight of sacred meeting grounds that the Algonquin peoples have always called Asinabka, or "Place of Glare Rock." (Report to Canadians, 2008, House of Commons)
Champlain had also encountered the Rideau Falls, the Rideau River's most northerly point where it empties into the Ottawa River. Much of the early settlement took place between the falls, located east of Parliament Hill, and the Chaudière Falls, in the west, in what would first become Bytown, and later the city of Ottawa. The falls were named by the early French (possibly Champlain in 1613) for their resemblance to a curtain (or rideau in French). The Rideau River was later named after the falls. The Rideau Canal would later bypass these falls and provide transportation to immigrants and goods. Champlain wrote:
There is an island in the centre, all covered with trees, like the rest of the land on both sides, and the water slips down with such impetuosity that it makes an arch of four hundred paces; the Indians passing underneath it without getting wet, except for the spray produced by the fall."
The early explorers, hoping to profit from the fur trade, had accomplished what Jacques Cartier was unable to do, where he was blocked near Hochelaga's Lachine Rapids, near present day Montreal. From 1613 to 1663, a royal charter from the King of France gave the successive groups monopolies to invest in New France territories and control of the fur trade and colonization. The Hudson's Bay Company formed in 1670 used the Ottawa River and its tributaries as the local conveyance for the delivery of fur products to Europe through Montreal and Quebec City.
Other missionaries, coureurs de bois and voyageurs passed through the area, such as Jesuit martyr Jean de Brébeuf in 1634, on his way to the Hurons (Wyandot people), Groseilliers in 1654, Radisson, and in the 1700s explorers Vérendrye in 1742, and later Alexander Mackenzie, as well as Joseph Frobisher and Simon McTavish. Nicholas Gatineau also traded using the nearby Gatineau River.
The Algonquin were not the only people in present day Ontario. During the 17th century, the Algonquians and Hurons fought a bitter war against the Iroquois. Champlain's travels brought him to Lake Nipissing and Georgian Bay to the center of Huron country near Lake Simcoe. During these voyages, Champlain aided the Hurons in their battles against the Iroquois Confederacy. As a result, the Iroquois would become enemies of the French and be involved in multiple conflicts (known as the French and Iroquois Wars) until the signing of the Great Peace of Montreal in 1701.