In order to find his arrival and naturalization record, we would need to know his name, approximate year of birth, and where he resided in the US.
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We searched the National Archives Catalog and located Passenger and Crew Lists of Vessels Arriving at New York, New York, 6/16/1897 - 7/3/1957 (T715) in the Records of the Immigration and Naturalization Service (Record Group 85) that may include the lists of Sobieski for 1947. Some of these records have been digitized and are available using the Catalog. For information about the non-digitized records, please email the National Archives at Washington, DC - Textual Reference (RDT1) at email@example.com.
The National Archives holds Naturalization records filed in the Federal District/ Circuit Courts. These records are arranged by the states in which the courts existed and are held by the regional NARA facilities for that state. Researchers should contact the National Archives facility serving the state in order to assist them in locating the records that they are seeking.
Due to the COVID-19 pandemic and pursuant to guidance received from the Office of Management and Budget (OMB), NARA has adjusted its normal operations to balance the need of completing its mission-critical work while also adhering to the recommended social distancing for the safety of NARA staff. As a result of this re-prioritization of activities, you may experience a delay in receiving an initial acknowledgement as well as a substantive response to your reference request from RDT1. We apologize for this inconvenience and appreciate your understanding and patience.
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