Most Dakota County cities were previously townships or unincorporated villages before officially incorporating as cities. Some incorporated as villages first, then became cities in 1974 when all Minnesota villages were switched over to city status. These dates reflect the earliest incorporation dates for Dakota County cities or villages.

Hastings 1857

Farmington 1872

Rosemount 1875

Mendota 1887

South St. Paul 1887

Mendota Heights 1956

Sunfish Lake 1958

Inver Grove Heights 1965

Lakeville 1967

Apple Valley 1968

Eagan * 1972

* Eagan Township was founded in 1860, and the city held a 150th anniversary celebration in 2010 in recognition of the township's beginnings.

Sources: Dakota County Historical Society, city websites