Please note that the content of this book primarily consists of articles available from Wikipedia or other free sources online. Seth Williams (March 22, 1822 March 23, 1866) was an American military figure who served as assistant adjutant general of the Union''s Army of the Potomac during the American Civil War. Williams was born in Augusta, Maine. He graduated from the United States Military Academy in 1842, 23rd in a class of 56. He served as aide-de-camp to General Robert Patterson in the Mexican-American War with the rank of second lieutenant. Williams received a brevet to the rank of captain for his conduct at the Battle of Cerro Gordo as a first lieutenant. He was adjutant at West Point from 1850 to 1853 before moving to the adjutant general''s office in Washington, D.C.