According to Latter Day Saint movement founder Joseph Smith, Adam-ondi-Ahman, situated in the central part of the county, was where Adam and Eve relocated after being banished from the Garden of Eden.

In 1838, two years after the county was organized, Joseph Smith's claims about the history of the area spurred in an influx of Mormon settlers.

Non-Mormon residents feared they were going to lose control of the county and attempted to prevent Mormons from voting in the Gallatin Election Day Battle.

Later, in retaliation for violence to their families and destruction of their property, some Mormons burned and sacked Gallatin, Grindstone Fork, Millport and other smaller settlements.

[6] Missouri Governor Lilburn Boggs issued an Extermination Order to drive the Mormons from the state after arresting Joseph Smith and other leaders of the church.

The first confirmed bank robbery involving Jesse James occurred on December 7, 1869, at the Daviess County Savings Association in Gallatin.

[7] The Daviess County Savings Association and the Gallatin Opera House have since been torn down, although the Winston Rock Island Line train station still stands and is operated by the local historical society as a museum.

Daviess County, along with the rest of the state of Missouri, is represented in the U.S. Senate by Josh Hawley (R-Columbia) and Roy Blunt (R-Strafford).

Like most rural areas throughout northwest Missouri, voters in Daviess County generally adhere to socially and culturally conservative principles which tend to influence their Republican leanings, at least on the state and national levels.

On the Democratic side, former Vice President Joe Biden (D-Delaware) both won statewide and carried Daviess County by a wide margin.

Incumbent President Donald Trump (R-Florida) faced a primary challenge from former Massachusetts Governor Bill Weld, but won both Daviess County and statewide by overwhelming margins.

Businessman Donald Trump (R-New York) narrowly won the state overall, but carried a majority of the vote in Daviess County.

On the Democratic side, former Secretary of State Hillary Clinton (D-New York) both won statewide and carried Daviess County by a small margin.

Senator Rick Santorum (R-Pennsylvania), who finished first in the state at large, but eventually lost the nomination to former Governor Mitt Romney (R-Massachusetts).

In 2008, the Missouri Republican Presidential Primary was closely contested, with Senator John McCain (R-Arizona) prevailing and eventually winning the nomination.

Then-Senator Hillary Clinton (D-New York) received more votes than any candidate from either party in Daviess County during the 2008 presidential primary.

Despite initial reports that Clinton had won Missouri, Barack Obama (D-Illinois), also a Senator at the time, narrowly defeated her statewide and later became that year's Democratic nominee, going on to win the presidency.