Background
William Henry Sidell, the son of John Sidell, was born in New York City.
William Henry Sidell, the son of John Sidell, was born in New York City.
He received an appointment to the United States Military Academy from New York on July 1, 1829, and was graduated four years later, standing sixth in a class of forty-three.
He was commissioned brevet second lieutenant of the 16t Artillery, but, disappointed at not having been assigned to the engineer corps, he resigned from the army on October 1, 1833, and took up the profession of civil engineer.
For four years he served successively as city surveyor in New York City, as assistant engineer on the Croton aqueduct, as division engineer of the Long Island Railroad, and as assistant engineer on projected dry docks in New York harbor.
From 1837 to 1839 he was an engineer on the United States hydrographic survey of the delta of the Mississippi, and subsequently, until 1846, served as a civil engineer of various railroads in New York and Massachusetts.
During the Mexican War he accepted a captaincy in the 4th New York Volunteers, but his regiment was never mustered into the federal service. From 1846 to 1849 he was with the Isthmus (of Panama) Railroad, becoming during the last year of his service its chief engineer. For the next two years he was in the United States service, exploring for a railroad route from the Mississippi to the Pacific.
In 1851-52 he was engaged in the surveying of a railroad route across the isthmus of Tehuantepec in Mexico. Thereafter he was chief engineer of various railroads in Illinois and Missouri until 1858, when he returned to Mexico as chief engineer of the Louisiana Tehuantepec Company, to complete the difficult survey of the transisthmian railroad route on which he had been engaged some years earlier. When the Civil War broke out, he at once offered his services to the Union, and, May 14, 1861, was commissioned major of the 15th Infantry in the regular army and assigned to recruiting duty in Kentucky and Tennessee.
In 1862 he was appointed acting assistant adjutant-general of the department of the Cumberland, and in 1863, acting assistant provost-marshal-general for Kentucky and general superintendent of recruiting and chief mustering and disbursing officer at Louisville, Kentucky, which positions he held to the end of the war.
On May 6, 1864, he was promoted to lieutenant-colonel, 10th Infantry.
He was brevetted colonel, May 13, 1865, for meritorious and faithful services in the recruitment of the armies of the United States, and on the same date, brigadier-general for faithful and efficient services during the war. He was on frontier duty in the Dakotas and in Kansas for the most of the time until 1870, when he was retired from active service for disability contracted in line of duty. He died at the home of his sister, Mrs. Jasper Grosvenor, in New York City.