Union soldiers who were paroled after their capture by Confederate Lieutenant General Thomas J. "Stonewall" Jackson at the Battle of Harpers Ferry, Virginia (later West Virginia) on September 15, 1862, were sent to Camp Douglas for temporary detention. Under the terms of the prisoner cartel, they had to await formal exchange before they could leave the camp. These 8,000 paroled Union soldiers began to arrive at Camp Douglas on September 28, 1862. Brigadier General Daniel Tyler relieved Colonel Tucker of command of the camp. Under Tyler's command these Union soldiers had to live under similar conditions to those endured by the Confederate prisoners from Fort Donelson. In fact, the conditions were worse because the camp had become filthy and even more run down during its occupancy by the prisoners. The paroled soldiers were fortunate to have only about a two-month stay. They were able to tolerate the conditions somewhat better than the previous Confederate prisoners could because the Union parolees were more warmly dressed and in better physical condition. The damp conditions and bad food still took their toll on the parolees. By November, forty soldiers of the 126th New York Volunteer Infantry Regiment were dead and about another sixty were ill with fevers. Soon after Tucker's resignation from the Illinois militia, Brigadier General Jacob Ammen became the camp commander.