French traders, Jacob Franks of Green Bay, and Franks' clerk, Jacques Poltier, visted Fond du Lac as early as 1787 establishing a trading post at the forks of the Fond du Lac river. The name Fond du Lac is a French term meaning 'farthest end of the lake'.
Fond du lac County, through the first third of the nineteenth century, was part of the Winnebago Indian nation. However in November, 1835, a number of prominent men of the Green Bay area, lead by James Duane Doty, joined themselves into an organization known as the Fond du Lac Company, for the purpose of buying and selling land shares at the foot of Lake Winnebago, which at the time resided in the county of Brown, Wisconsin Territory. By January 1836, the company had accumulated 3,705 acres of land, selling 300 land shares at $100 each, all of which currently lie within the city of Fond du Lac. Doty had an interest in the transportation possibilities of Lake Winnebago and the construction of a canal to the Rock River at the Horicon marsh and another to Sheboygan on Lake Michigan.
The county itself was created in 1836, the year that the first permanent settlers, Colwert and Edward Pier, arrived. By the close of the 1830's this central Wisconsin wilderness became a focal point for easterners hoping to create new lives for themselves. The eventual city of Fond du Lac, which historian Joseph Schafer refers to as "the first location to be exploited entirely for speculative purposes," was effectively created by James Duane Doty, the Wisconsin territory's premier speculator. Through Doty's lobbying efforts, the prospective city was made a candidate for the new Wisconsin territorial capital, although there were fewer than 140 white settlers in the entire county as late as the federal census of 1840.
Growth came rapidly beginning in the mid-1840's, as Yankees began arriving by the thousands to rebuild the homes, farms, and communities they knew in New England, New York, and Pennsylvania. By 1850, the county's townships were established. In far western Fond du Lac County, the population of Metomen, first settled in 1844, grew from 460 in 1847 to 720 by 1850 and 1617 by 1860. By 1870, Fond du Lac was the state's second largest city, a major railroad hub, and the county was second only to Dane in wheat production.