Nathan Nabors

From the NARA's Registers of Enlistments in the United States Army, 1798-1914:

Source - Fold3

Sergeant, 3rd U.S. Infantry

December 8, 1808

Captain Joseph Woodruff

Colonel Hampton

December 19, 1809
...3rd U.S. Infantry Regiment, who has come to Charleston from Rocky Mount with two companies of regulars under Capt. Joseph Woodruff and Lt. Benjamin Herriott....

My 4th great-grandmother was Rebecca Neighbors/Nabors.  Related to Nathan?  I don't know.

Leavenworth Portrait

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Henry Leavenworth

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Mr. Rogers Who Was A British Soldier

Among the Letters Received By the Adjutant General, 1805 - 1821, was a letter to Secretary of War Henry Dearborn from William Rogers (and also one to President James Madison), who had served in the British military, and wanted an appointment in the U.S. Military in 1811.  His siblings lived in the United States and he had married a Quaker woman.

Harrisburgh, Pennsylvania  30 April 1811

Source

"Being in London in 1797 I entered into the British Military Service in a Battalion of Infantry...".