Pender entered West Point in 1850 at age 16. He graduated in 1854, ranked 19th out of 46 in his class. He was commissioned in the Artillery.
He went to serve with the 1st U.S. Dragoons, mostly on the Pacific Coast. Pender was married and had 3 sons, all who survived him after his death.
Pender resigned his U.S. Army commission on March 1861 to join the Confederacy. He was one of the first Southerners to join the Confederacy.
He became a Colonel with the 3rd North Carolina Infantry and quickly gained a reputation as a hard-hitting commander.
He was promoted to Brigadier General in June 3, 1862 due to his gallant conduct during the Peninsular Campaign. He was promoted to major general on May 27, 1863. Pender was put in command of his own division in III Corps before Gettysburg.
On the 2nd day of the Battle of Gettysburg,
he was hit in his thigh by a small piece of shell fragment. At the time, he didn't think much of the injury and didn't seek any medical attention. When Gen. Robert E. Lee's army was back in Virginia, his wound had a massive infection that had spread through his leg. His leg was amputated, but he didn't survive the surgery. His remains were buried at the cemetary at Cavalry Church in Tarborough, North Carolina.
Pender was thought of as one of the best fighting generals in the Army of Northern Virginia.