Dear Mr. Faris,
Thank you for posting your request on History Hub!
The United States Army did not have any infantry divisions in 1859. We presume you mean the 3rd Infantry Regiment. We searched the National Archives Catalog and located the series Muster Rolls of Regular Army Organizations, 1784 - 10/31/1912 in the Records of the Adjutant General's Office, 1762 - 1917 (Record Group 94) that may include rolls for the 3rd Infantry Regiment in 1859. We also located 10 record series created by the 3rd Infantry Regiment in the Records of U.S. Regular Army Mobile Units (Record Group 391) that include records from the 1850s. For more information about these records, please email the National Archives at Washington, DC - Textual Reference (RDT1) at email@example.com.
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We hope this is helpful. Best of luck with your research!