The Expedition That Put Chicago on the Map
In the summer of 1673, a small party of seven men in two birch-bark canoes set out from the mission of St. Ignace at the northern tip of Lake Michigan on a journey that would fundamentally alter European understanding of the North American interior. The expedition was led by Louis Jolliet, a thirty-year-old French-Canadian fur trader, cartographer, and musician who had been educated by Jesuits in Quebec and trained in hydrography at the royal court in France. His companion was Father Jacques Marquette, a Jesuit missionary fluent in six Native American languages who had spent the previous five years establishing missions among the peoples of the upper Great Lakes. Together, they had been commissioned by the Intendant of New France, Jean Talon, and the Governor, the Comte de Frontenac, to find the great river that Native informants described flowing southward through the heart of the continent and to determine whether it emptied into the Gulf of Mexico, the Pacific Ocean, or the Gulf of California.
Their route took them westward along the northern shore of Lake Michigan, through the Straits of Mackinac, and down Green Bay to the Fox River. From the Fox they portaged to the Wisconsin River, and on June 17, 1673, they entered the Mississippi, becoming the first Europeans to document the upper reaches of the river system with any cartographic precision. They traveled south as far as the mouth of the Arkansas River, where encounters with armed indigenous groups and evidence of Spanish colonial presence persuaded them that the river did indeed flow to the Gulf of Mexico. Satisfied that continuing south would risk capture by the Spanish without adding materially to their geographical knowledge, they turned north.
It was on the return journey that the expedition made the observation that would prove most consequential for the future city of Chicago. Native guides informed Jolliet and Marquette of a shorter route back to Lake Michigan, one that avoided the lengthy detour through the Wisconsin and Fox rivers. This route followed the Illinois River upstream to a tributary called the Des Plaines, and from the headwaters of the Des Plaines a short overland portage of only a few miles led to a sluggish river flowing east into Lake Michigan. That river, lined with marshes thick with wild leek and garlic, was called "Checagou" by the indigenous peoples of the region, and it is from this word that the modern city takes its name.
Mapping "Checagou": The Portage That Changed Everything
Jolliet recognized immediately that the Chicago portage was a geographical feature of extraordinary strategic importance. In an era when water was the primary medium of long-distance transportation, a short overland crossing connecting the Great Lakes to the Mississippi River system meant that it was theoretically possible to travel by canoe from the mouth of the St. Lawrence on the Atlantic coast all the way to the Gulf of Mexico with only a single brief portage. Whoever controlled that portage controlled the most efficient trade and military route through the interior of the continent.
Jolliet's map recorded this portage with notable care, showing the relative positions of the Des Plaines River, the short overland crossing, and the river flowing into Lake Michigan. The map used a combination of observed geographical features and information gathered from indigenous informants, a standard practice in colonial-era cartography that often produced surprisingly accurate results. The rendering of the Chicago area, while schematic by modern standards, correctly identified the critical hydrological relationship between the two watersheds and positioned the portage with sufficient accuracy to guide subsequent French expeditions to the site.
The name "Checagou" appeared on the map in the French orthography of the period, and scholars have debated its exact indigenous etymology for more than a century. The most widely accepted interpretation traces it to a word in the Miami-Illinois language referring to wild leek or ramp (Allium tricoccum), a pungent plant that grew abundantly in the marshy ground near the lakeshore. Other theories connect the name to a powerful local chief, to the striped skunk, or to a broader Algonquian term for "strong" or "great." Whatever its precise origin, the name stuck. From Jolliet's 1673 map forward, every European cartographer who depicted the southwestern shore of Lake Michigan labeled the area with some variation of "Chicagou," "Checagou," or "Chikago."
The Loss of the Original Map
The story of Jolliet's map is inseparable from the story of its near destruction. After completing the expedition, Jolliet traveled east toward Montreal to report his findings to the colonial authorities. In the spring of 1674, as his canoe shot the Lachine Rapids on the St. Lawrence River just upstream from Montreal, the vessel capsized. Jolliet was thrown into the violent current and nearly drowned. Two of his companions perished. When he was finally pulled from the water, he had lost everything: his maps, his journals, his collected specimens, and the detailed notes he had compiled over the course of more than a year of travel. The cartographic record of one of the most important North American expeditions of the seventeenth century was gone.
What survives today is a reconstruction. Jolliet drew a new map from memory after his rescue, and Marquette independently recorded details of the journey in his own journal before his death in 1675. Additional copies and derivatives were produced by French colonial cartographers working from Jolliet's verbal accounts and from Marquette's written records. The most significant surviving version is held in the archives of the Service hydrographique de la marine in Paris, and it has been the subject of extensive scholarly analysis. Researchers have compared its details against later, more precise surveys and found that Jolliet's memory-based reconstruction was remarkably accurate, particularly in its depiction of the Chicago portage and the relationship between the Illinois River system and Lake Michigan.
French Territorial Claims and the Strategic Portage
The map Jolliet produced was not merely a geographical document; it was a political instrument. In the competitive imperial landscape of seventeenth-century North America, maps served as evidence of discovery, exploration, and territorial claim. By documenting the Chicago portage, Jolliet provided the French Crown with a cartographic basis for asserting sovereignty over the heart of the continent. The portage connected two of the most important waterway systems in North America, and French control of that connection was central to the colony's strategy of containing British expansion west of the Appalachian Mountains.
The strategic significance of the portage was not lost on French administrators. In 1682, Rene-Robert Cavelier, Sieur de La Salle, used the Chicago portage on his famous expedition down the Mississippi to the Gulf of Mexico, during which he claimed the entire Mississippi River basin for France and named it Louisiana. Subsequent French maps of the period prominently featured "Chicagou" as a key node in the network of forts, missions, and trading posts that constituted New France's inland empire. The area appeared on Guillaume Delisle's influential 1718 map of Louisiana, on Jacques-Nicolas Bellin's detailed 1744 map of the Great Lakes, and on numerous other French cartographic productions throughout the colonial period.
Comparing the 1673 Map with Later Surveys
One of the most fascinating exercises in Chicago's cartographic history is comparing Jolliet's 1673 depiction with the maps produced over the following two centuries. The differences illuminate both the evolution of surveying technology and the transformation of the landscape itself.
Jolliet's map showed a landscape of rivers, marshes, and prairies with no permanent structures, no roads, and no cultivated fields. The 1830 plat drawn by James Thompson for the Illinois and Michigan Canal Commission depicted the same area divided into a grid of rectangular lots, with streets named and numbered, ready for sale to speculators and settlers. By the time the Sanborn fire-insurance company began mapping Chicago in the 1860s, the former portage was buried beneath a dense urban fabric of warehouses, rail yards, lumber mills, and tenement houses. Each successive map recorded not just the growth of a city but the erasure of the natural geography that had made the city's location significant in the first place.
Yet the ghost of the portage persists. The Chicago Sanitary and Ship Canal, completed in 1900, follows approximately the same route that Jolliet's indigenous guides showed him in 1673. The engineered waterway reversed the flow of the Chicago River and created the permanent navigable connection between the Great Lakes and the Mississippi that nature had only hinted at through the seasonal flooding of the portage. In a sense, the modern canal fulfilled the geographical promise that Jolliet identified on his map more than two centuries earlier.
The Legacy of the First Chicago Map
Jolliet's 1673 map occupies a unique position in the history of Chicago. It is the document that brought the area to the attention of European powers, established the name that the city still bears, and identified the geographical advantage that would eventually draw millions of people to a stretch of marshy lakeshore that seemed, on the surface, to offer little reason for settlement. Every subsequent Chicago map, from Thompson's 1830 plat to Burnham's 1909 plan to the latest GIS rendering, is in some sense a descendant of Jolliet's hand-drawn reconstruction.
For collectors and historians, reproductions of the Jolliet map are among the most meaningful pieces in any Chicago cartographic collection. They represent the moment when the city's story began to be recorded in a medium that could be shared, studied, and preserved. At Earliest Chicago Maps, we produce museum-quality giclée reproductions of the Jolliet map on archival cotton rag paper, faithfully reproducing the tonal character of the original document. Each reproduction comes with a certificate of provenance identifying the source document and its archival holding, and we offer conservation-grade framing to ensure the piece is protected for future generations.
The story of Chicago's first map is, in many ways, the story of the city itself: improbable, resilient, and shaped by the intersection of geography and human determination. A young explorer nearly drowned, lost his life's work, and then sat down and drew it all again from memory. The map he produced pointed the way to a portage that pointed the way to a city that would become one of the most consequential urban centers in the Western Hemisphere. It is a story worth knowing, and a map worth owning.
Frequently Asked Questions
Who created the earliest known map of Chicago?
The earliest known cartographic depiction of the Chicago area was created by French-Canadian explorer Louis Jolliet following his 1673 expedition with Father Jacques Marquette. Jolliet's original map was lost when his canoe capsized in the Lachine Rapids near Montreal, but he reconstructed it from memory and the surviving version is held in French archives.
What did the 1673 Jolliet map show about Chicago?
The 1673 Jolliet map depicted the Chicago portage, the critical overland connection between the Great Lakes watershed and the Mississippi River system. It showed the Des Plaines River, the Chicago River, and the short portage path between them, labeling the area "Checagou" after the indigenous name for the wild garlic or onion plants that grew in the marshy terrain.
Why was the Chicago portage so important to early explorers?
The Chicago portage was vital because it provided the shortest overland route connecting the Great Lakes to the Mississippi River system. This meant that travelers and traders could move goods between the St. Lawrence Seaway and the Gulf of Mexico with only a brief land crossing. Control of this portage gave enormous strategic and commercial advantage, which is why the French, British, and eventually Americans all sought to dominate the area.
How was the original Jolliet map lost?
Louis Jolliet's original map and expedition journals were lost in 1674 when his canoe overturned in the Lachine Rapids on the St. Lawrence River near Montreal. Jolliet nearly drowned and lost all of his papers, specimens, and notes. He subsequently reconstructed the map from memory, and it is this reconstructed version that survives in archival collections today.
Where can I see reproductions of the 1673 Chicago map?
Authenticated reproductions of the 1673 Jolliet map are available through Earliest Chicago Maps. Our gallery at 714 South Dearborn Street in Chicago's Printer's Row neighborhood carries museum-quality giclée reproductions printed on archival cotton rag paper. We also offer custom framing services to present these historic documents in conservation-grade materials.
