Daniel P. Tyler IV (January 7, 1799 – November 30, 1882) was an iron manufacturer, railroad president, and one of the first Union Army generals of the American Civil War.

[1][2] He became an authority on artillery and an honest inspector of arms of private contractors, which appears not to have helped him advance above first lieutenant in rank.

[4] Tyler resigned his commission in the United States Army in May 1834 and became an iron manufacturer, developing blast furnaces and rolling mills.

[1][5] Though he has been assigned a substantial portion of the blame for the Union disaster at Bull Run, he was appointed to the rank of brigadier general of volunteers on March 13, 1862.

[1][5] At the Battle of Harpers Ferry on September 15, 1862, a large number of Union troops surrendered to the forces of Confederate General Thomas J.

[6] Under Tyler's command these Union soldiers had to live under similar conditions to those endured by the Confederate prisoners from Fort Donelson.

[1][5] Tyler resigned his commission in the Union Army on April 6, 1864, then being older than the retirement age of 65,[1] and moved to New Jersey.