Connecting census records, passenger lists, and naturalization papers


Fig.1 Census Record in

When piecing together the clues of your family tree, it’s exciting to find one or more family members listed in documents as historic as census records or passenger lists, but don’t let the celebration of your discovery distract you from gleaning all you can from these records.  There are sometimes subtle, but important clues that tie census records, passenger arrival records, and naturalization papers to one another.  Knowing where to look and what to do with the clues you find can help save you a tremendous amount of time in your ongoing search.

Census Records

As discussed in other articles about U.S. Census Records, there can often be more than a dozen and sometimes as many as 50 individual data elements listed for each individual.  The census questions changed from year to year and the wording varied slightly, but a careful inspection of census records can yield clues pointing you directly to passenger lists or naturalization files.  The U.S. census was conducted every ten years, beginning in 1790.  With each passing decade, the effort became more refined and questions captured additional detail helpful to government officials for one reason or another.  Among the questions, a few were directed at citizenship and understanding the status of foreign-born persons listed within.  Some of the more important questions and their corresponding census years were: 

  • Number of years in the United States (1890, 1900)
  • Whether naturalized or an alien living in the United States (1890-1940)
  • For non-citizens, whether naturalization papers have been filed (1890, 1900, 1910, 1940)
  • If foreign-born, year of immigration to the United States (1900-1930)
  • If foreign-born and Naturalized, year of Naturalization (1920)

Interpreting the answers, sometimes expressed as codes (e.g. – ‘Na’ for Naturalized, ‘Pa’ for having first papers, ‘Al’ for Alien, or ‘Am Cit’ for American Citizen born abroad), can be the key to unlock your next document.

Passenger Lists

If you are an American in search of your family roots, it is likely that at least one of your ancestors is an immigrant from some point in history.  The peak period of immigration began in 1892 and continued through the mid-1920s, but there were arrivals before and after that time as well.  Many American’s today – as many as 40% - can trace at least one line of their family through an Ellis Island arrival.  Some census records, notably 1890-1930, asked questions which enable one to pinpoint the year of arrival for their immigrant ancestors.

Similarly, if you have a passenger arrival record, but have not yet looked for or found your ancestors in U.S. census records, you can use the date of arrival to help direct your efforts.  By way of example, if your ancestor arrived through the Port of New York in 1897, then you should look in the 1900 U.S. census records.  For arrivals in the early 1900s, start your search using the 1910 U.S. census.

Naturalization Papers

In much the same way that census records can help point you to passenger lists, the same can be said for documents contained in a naturalization files.  Depending upon the year of arrival and how quickly your ancestors filed their first papers, the details contained in naturalization files can be among the most data-rich for any immigrant family.  Files will often contain a Declaration of Intention, Petition for Citizenship, Certificate of Arrival, and an Oath of Allegiance.  The collection of papers contained within each file can include detailed lists of family members, dates and places of birth, names of relatives in the United States as well as in their country of origin, and the names of witnesses.

Census records can provide clues as to the status of the naturalization process.  The 1940 census, for example, asks in column 16, “Citizenship of the foreign born.”  If the response indicated ‘Na’ then your search for naturalization papers would need to focus on the period prior to April 1, 1940.  By looking at the 1930 census, column 23, you could then verify if the naturalization occurred prior to or after that date, further narrowing your search.  If the response in 1940 indicates ‘Pa’ then initial papers have been filed and the citizenship process is under way, but has not yet been finalized.

Connecting the dots

As you can see, these three record types – each created for very different reasons – are closely tied to one another from the perspective of family history research.  While it is tempting to celebrate the success of your discovery and then look for another person in the same record source while you’re on a ‘hot streak,’ you should be certain to look at every clue which ties your discovery to other data-rich sources.

By connecting the dots from census records to passenger lists and naturalization files, you will be able to develop a more complete picture of your ancestor, as well as their nuclear family and the previous generation as well.