Dubuque was French Canadian, and had (by most accounts) a friendly relationship with the local Meskwaki people.

When lead deposits began becoming exhausted, the pioneers developed boat building, lumber yards, milling, brewing, and machinery manufacturing to take its place.

At an extra session of the Sixth Legislative Assembly of Michigan Territory held in September 1834, the Iowa District was divided into two counties by running a line due west from the lower end of Rock Island in the Mississippi River.

The land in present day Minnesota and the Dakotas was transferred to the newly created Fayette County in this action.

In the 1980s, the farm crisis set in, and devastated large sections of the Midwest, including Dubuque County.

The county experienced huge population losses during this time, as workers left the area.

It would not fully recover from this until the late 1990s, when the economy diversified, shifting away from manufacturing, and toward various service-related establishments.

The surging economy can especially be seen in the West Side of the City of Dubuque, and in neighboring Peosta and Asbury.

These areas have expanded so much that concerns now lie with trying to manage the growth, a sharp change from just 20 years ago.

Current supervisors include Ann McDonough, Wayne Kenniker and Harley Pothoff (chairperson).

The city of Dubuque and surrounding areas adjacent to the Mississippi River have many steep hills, bluffs, and ravines.

During the last ice age, much of the Mississippi Valley near Dubuque County was bypassed by glacial flows, which flattened the surrounding land in eastern Illinois, Wisconsin, and western Iowa, leaving the Driftless Area unusually rugged.

2005 estimates by the census indicated that Dubuque had a population that identified itself as being 95.5% non-Hispanic white, 1.3% African American, 0.7% Asian and 1.5% Latino.

Now, alongside manufacturing, which still employs thousands of workers, many county residents work in the tourism/gaming, health care, education, publishing, and financial service sectors.

With the exception of industrial areas in Cascade, Dyersville, and Peosta, almost all of the rest of the county is rural and agriculturally driven.

Dubuque County has, in recent years, enjoyed job growth, low unemployment, and the rapid expansion of business and commerce.

[23] In 2016, it was narrowly won by Donald Trump, who became the first Republican to win the county since President Eisenhower in 1956.

In the 2022 elections, the county continued to trend rightward, with Republican governor Kim Reynolds winning reelection by a margin of over 16 points.

Tertiary education: K-12 school districts include:[26] As of 2022[update], Dubuque County has a large percentage of Catholic residents.