What occasionally happened is they just never got around to it. Just got busy with the farm or business similar to what happens to all of us from time to time. Sometimes they moved to a different area prior to becoming naturalized. But most often I would guess they had it done in a federal court. If this is the case then the records would reside in the nearest seat of the court. You might check with the Indiana genweb site and see if they have it listed. Terri