John Lonergan (April 7, 1839–August 6, 1902) was a captain in the Union Army and a Medal of Honor recipient for his actions in the Battle of Gettysburg during the American Civil War.

Rank and organization: Captain, Company A, 13th Vermont Infantry.

Place and date: At Gettysburg, Pa., July 2, 1863.

Citation: Gallantry in the recapture of 4 guns and the capture of 2 additional guns from the enemy; also the capture of a number of prisoners.

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