The settlers of East Donegal were of Scots-Irish descent and were primarily farmers who were drawn to the area by the rich soils and plentiful streams.

Thus the abundant produce provided by the land was able to be made into flour by the many mills which sprang up in the area.

Bartram Galbraith, grandson of James Galbraith, was Lieutenant for Lancaster County, the first three years of the Revolution, and many members of that family served in various official positions, as also did Alexander Lowrey and several of that family.

The Chickies Historic District, Donegal Presbyterian Church Complex, Grove Mansion, Donegal Mills Plantation, Byers-Muma House, and Cameron Estate are listed on the National Register of Historic Places.

The borough of Marietta, a separate municipality, is on the southern border of the township and occupies land formerly belonging to it.

16.1% of all households were made up of individuals, and 4.8% had someone living alone who was 65 years of age or older.