Dennis Hart Mahan (Mă-hăn) [məˈhæn] was a noted American military theorist, civil engineer and professor at the United States Military Academy at West Point from 1824–1871. He was the father of American naval historian and theorist Rear Admiral Alfred Thayer Mahan.

George Brinton McClellan was an American military officer and politician who served as the 24th governor of New Jersey and as Commanding General of the United States Army from November 1861 to March 1862. He was also an engineer, and was chief engineer and vice president of the Illinois Central Railroad, and later president of the Ohio and Mississippi Railroad in 1860.