[2] The first settler of Bethel Township was John Gibson, a native of the state of North Carolina, who settled in 1829, on section two.

He built the first house within the limits of the present township near the village of Middletown.

Among other earliest settlers of Bethel township between 1829 and 1835 were: Benjamin Matthews, James H. Dunsworth, Charles Dunsworth, James Edmonston, John Venard, William Venard, Malachi Monk, John Monk, Martin Fugate, John W. Fugate, James C. Archer, Thomas F. Shoopman, William I.

It was originally known as Eagle township, but was changed to its present cognomen at the first meeting of the board of supervisors in May, 1857.

[4] According to the 2010 census, the township has a total area of 36.64 square miles (94.9 km2), all land.