It was named for American Revolutionary war soldier Cornelius Harnett,[6] who was also a delegate to the Continental Congress.

The Scots settled in the foothills, where land was more affordable, rather than in the rich alluvial soil area of the coastal plain.

After the defeat by the British of Bonny Prince Charles at Culloden, Scots immigrants came up the Cape Fear River in ever increasing numbers and settled in western Harnett County.

British immigrants had settled primarily along the banks of the Cape Fear River in the coastal area, generally from Erwin to Wilmington.

[8] Though Harnett County was not a site of warfare during the Civil War, one of the last battles took place near Averasborough, which was once the third-most populated town in North Carolina, but is no longer in existence.

Apart from the 1928 election when it defected to Herbert Hoover because of opposition to the Catholicism of Al Smith,[20] Harnett voted rock-solid Democratic until the 1960s when opposition to increasing liberalism on racial policies turned the electorate toward the segregationist candidacy of George Wallace.