What county in southern Ohio? My great great grandmother was Emily Icenogle, who grew up in Washington County, Decatur Twp. She married Conrad Miller in 1861. Her parents were Henry and Anne (Knox) Icenogle, who originally were from Carroll Co. Ohio, and before it became Carroll, Jefferson Co. I have some information on the Icenogles of Washington Co. and before.
I have seen the surname spelled at least 8 different ways, so remember to check all possible spellings!