i am looking for a Certificate of Non Existence for my Great Grandfather

Question

I have a preliminary letter stating Non Existence from the National Archives of San Francisco 
 But is there another way to know that he did not naturalize before I request from the USCIS? 
 
 Thanks 
 Nicole

A1 Reference Branch · Answer

Nicole4B 
 Thank you for using the History Hub! 
 We receive many questions about locating naturalization records. You may find the following previously answered question helpful: 
 How do I find my ancestor&rsquo;s certificate of naturalization? 
 We also have a page for those who are looking for information required for dual citizenship application: https://www.archives.gov/research/immigration/dual-citizenship-faq . 
 I hope this assists with your research! 
 Sincerely, Archives 1 Reference Branch (RR1R) [RR1R-24-42693-KS]