Not Every Immigrant Naturalized

If you cannot find a naturalization record for an ancestor, keep in mind that he might never have naturalized. If your ancestor did not want to vote, he might not have found being a citizen necessary. Back during the time when being an "alien" wasn't so much of a problem, "aliens" could own land, sell it, bequeath it, etc. If economics were the main reason for immigration, your ancestor might not have become a citizen.