Barclay Coppock (January 4, 1839-September 4, 1861) was a follower of John Brown and Union Army soldier in the American Civil War. Along with his brother Edwin, he participated in the raid on Harpers Ferry. In historic documents their last name was variously spelled "Coppock" or "Coppoc". The Coppoc brothers were raised in Springdale, Iowa, where they met Brown while he was raising support for his Kansas Anti-slavery raids. Edwin was hung in Charlestown, Virginia while Barclay eventually escaped to Canada; his flight was aided by Samuel Kirkwood the governor of Iowa, who refused to extradite him when Barclay was discovered hiding in Iowa. Barclay later joined the Union Army during the American Civil War. Barclay was killed in action when his train plunged into a ravine on the Platte River (Missouri). Confederate Raiders had cut through the supports of the train bridge, the incident now called the Platte Bridge Railroad Tragedy.