Shiloh is a census-designated place in Harrison Township in Montgomery County, Ohio, United States. It was delineated as a census-designated place at the 2000 census, at which time its population was 11,272. It was not delineated as a CDP at the 2010 census. It is located directly north of the city of Dayton and is part of the Dayton Metropolitan Statistical Ar…Shiloh is a census-designated place in Harrison Township in Montgomery County, Ohio, United States. It was delineated as a census-designated place at the 2000 census, at which time its population was 11,272. It was not delineated as a CDP at the 2010 census. It is located directly north of the city of Dayton and is part of the Dayton Metropolitan Statistical Area.