The official document proving you have acquired U.S. citizenship through naturalization is the Certificate of Naturalization, issued by U.S. Citizenship and Immigration Services (USCIS). This is a federal administrative act conducted by USCIS, an agency under the U.S. Department of Homeland Security, rather than a court-ordered name change. If your name or surname was changed as part of the formal naturalization process and is explicitly stated on your Certificate of Naturali