Seneca was founded in 1857. Landmarks include US Post Office-Seneca, Nemaha County Jail and Sheriff's House and Hand-Dug City Water Well. Seneca is the birthplace of John Riggins, football player.
- CountyNemaha County
- Population2,139 (2020 U.S. Census)
- Historic places4 on the National Register


































US Post Office-Seneca
Nemaha County Jail and Sheriff's House
Hand-Dug City Water Well
Seneca Main Street Historic District