According to military records, William Lee Monegan volunteered on April 26, 1861, in Company C of the 10th Regiment of the New York State (Volunteers). He enrolled in New York City to serve two years and was appointed Second Lieutenant. He mustered in as First Lieutenant on April 30th 1861. The regiment was sent to Virginia in late May 1861, and Monegan's company arrived on the steamer State of Georgia on or about June 7, 1861. Headquarters for the regiment were established at Camp Hamilton, near Fortress Monroe. However, Monegan, in his correspondence, states that the regiment spent a large portion between June 1861 and February 1862 within the walls of Fortress Monroe. While encamped at Fortress Monroe, Monegan witnessed the battle between the US Steam Battery Monitor and the Confederate iron clad CSS Virginia.
In May 1862, the regiment moved to Norfolk and then Portsmouth. On June 7, 1862, the regiment was attached to the 3d brigade, 2nd division, 5th corps, which it joined at Bottom's bridge on the Chickahominy River. The regiment was active in the Seven Days' Battles and was encamped at Harrison's Landing. In August, the regiment returned to Newport News. While encamped at Harrison's Landing, the records show that Monegan resigned his commission on July 12, 1862. Little to nothing is known of Monegan's life before or after the Civil War. His parents and brother Joseph lived in Williamsburgh, New York.
From the description of William Monegan letters, 1861-1885 1861-1862. (The Mariners' Museum Library). WorldCat record id: 775010558
