After the war, he purchased a ranch along the San Antonio River in Texas, and also became married in 1849.

During the American Civil War, Pyron served in Confederate Brigadier General Henry Hopkins Sibley's New Mexico Campaign, an invasion of New Mexico and Colorado with the goal of capturing the Southwest United States, including the Colorado gold fields and California.

He raised a company of cavalry for the Confederates at San Antonio, which served as Company B of John Baylor's Second Texas Mounted Rifles at Fort Lancaster and Fort Stockton.

Control of the pass would allow the Confederates to advance onto the High Plains and to make an assault on Fort Union, the Union stronghold along the invasion route northward over Raton Pass.

After the war, he lived on his ranch in San Antonio, Texas, and died on August 24, 1869.