 The county commissioners eventually established the townships, including Union (1820), Darby (1820), Mill Creek (1820), Jerome (1821), Paris (1821), Liberty (1822), Leesburg (1825), Allen (1827), Jackson (1829), York (1834), Washington (1836), Dover (1839), Claibourne (1834), and Taylor (1849), while they designated Marysville as the county seat.The town of Milford was established in 1816 by George Reed, Marysville in 1819 by Samuel Culbertson, Richwood in 1832 by Philip Plumber, Kingsville in 1834, Somerville in 1835, Watkins and Arbelia in 1838, Newton in 1838 by David Paul, York Center in 1841, Frankfort in 1846, Unionville in 1847, Pharisburg in 1847, New California in 1853, Dover in 1854, Union Center in 1863, Broadway in 1865, Pottersburg in 1869, Peoria in 1870, Magnetic Springs in 1879, and Claibourne in 1881.After the organization of the county by the Ohio Legislature, Marysville was designated as the seat of Union County.