[3] Johnstown Township was originally established in 1838 but was much larger.

As of the census[1] of 2000, there were 3,067 people, 1,206 households, and 915 families residing in the township.

There were 1,367 housing units at an average density of 38.8 per square mile (15.0/km2).

[citation needed] There were 1,206 households, out of which 29.6% had children under the age of 18 living with them, 66.2% were married couples living together, 5.8% had a female householder with no husband present, and 24.1% were non-families.

19.7% of all households were made up of individuals, and 5.4% had someone living alone who was 65 years of age or older.