Early life and service
Coster was born in New York City, New York. On April 17, 1861, just five days after the firing on Fort Sumter, he enlisted as a private in the 7th New York Militia, one of the first regiments to come to the defense of Washington, DC at the outbreak of the Civil War. He later enlisted in 1861 at age 24 as a first lieutenant in 12th U. S. Infantry. He served in Brig. Gen. George Sykes's division of V Corps in the Seven Days Battles, being commended by his superiors for his conduct at the Battle of Gaines' Mill on June 27, 1862.
On October 8, 1862, Coster was named colonel of the recently organized 134th New York Infantry Regiment. By December 31, 1862, the regiment belonged to Col. Orland Smith's 2nd Brigade of Maj. Gen. Adolph von Steinwehr's 2nd Division, XI Corps, Army of the Potomac. Coster's regiment participated in the Battle of Chancellorsville under Brig. Gen. Francis C. Barlow, who had been appointed brigade commander in place of Smith. During May 1863, Coster's regiment joined the 1st Brigade, 2nd Division, under Col. Adolphus Buschbeck. When Buschbeck went on leave on June 10, Coster became brigade commander. In that role he patrolled near Boonsboro, Maryland before marching to Gettysburg, Pennsylvania.
Maj. Gen. Oliver Otis Howard kept von Steinwehr's division in reserve on the first day of the Battle of Gettysburg, July 1, 1863, positioning it on Cemetery Hill. When the Union right flank north of town began to collapse, Howard permitted von Steinwehr to send Coster's brigade to cover its retreat. These Union troops took a position just north of the town, where they were deployed in a brickyard. The brigade was attacked by superior forces from the Confederate division of Maj. Gen. Jubal Early. Coster's brigade lost most of its 597 casualties in that action. The remainder of the brigade spent the next two days supporting batteries on Cemetery Hill. Howard commended Coster and other senior commanders by name for their courage and devotion to duty in his report on Gettysburg.
Later in 1863, Coster resigned his regimental command. On May 18, 1864, he was appointed a provost marshal for the State of New York to serve the Board of Enrollment. Coster resigned that position on April 30, 1865. Thereafter he lived in New York City. On February 28, 1882, he became a federal Pension Agent for the city, resigning effective December 1, 1885. He was also a member of the Grand Army of the Republic.
Coster died in New York City and was buried on December 26, 1888. He left a widow and children.
Coster Avenue, part of the Gettysburg Battlefield but within the town itself, has a brigade marker and three regimental monuments. A mural painting on the wall of a neighboring building commemorates the Confederate attack and Coster's defense.
- Historical Data Systems Civil War Database
- Conklin, George W. (1999). Under the Crescent and Star: The 134th New York Volunteer Infantry in the Civil War, p. 31. Axworthy Publishing. ISBN 0967498503.
- "134th NY Infantry Regiment during the Civil War". NY Military Museum and Veterans Research Center. http://www.dmna.state.ny.us/historic/reghist/civil/infantry/134thInf/134thInfMain.htm. Retrieved 2008-10-25.
- O.R., series I, vol. 27, pt. 1, p. 706.
- "Funeral of Col. Charles R. Coster.". New York Times. December 27, 1888. p. 8. http://query.nytimes.com/gst/abstract.html?res=9C0DE4DC163BE033A25754C2A9649D94699FD7CF. Retrieved 2008-10-25.
- "Coster Avenue Mural". Photo Album. Gettysburg, PA: Civilwaralbum.com. 2003. http://www.civilwaralbum.com/gettysburg/coster_mural1.htm#Enlarge. Retrieved 2008-10-25.
- "Funeral of Col. Charles R. Coster," The New York Times December 27, 1888.
- Conklin, George W., "Under the Crescent and Star: The 134th New York Volunteer Infantry in the Civil War", Port Reading, New Jersey: Axworthy Publishing, 1999, ISBN 0-9674985-0-3.
- Dyer, Frederick H., A Compendium of the War of Rebellion: Compiled and Arranged From Official Records of the Federal and Confederate Armies, Reports of the Adjutant Generals of the Several States, The Army Registers and Other Reliable Documents and Sources, Des Moines, Iowa: Dyer Publishing, 1908 (reprinted by Morningside Books, 1978), ISBN 978-0890290460.
- Pfanz, Harry W., Gettysburg—the First Day, Chapel Hill: University of North Carolina Press, 2001, ISBN 0-8078-2624-3.
- U.S. War Department, The War of the Rebellion: a Compilation of the Official Records of the Union and Confederate Armies, U.S. Government Printing Office, 1880–1901.