wyeth attended la grange military academy, a defunct military academy in colbert county, alabama, from the age of 15 to 17. during the american civil war of 1861-1865, he served in the confederate states army. he participated in morgan's raid under brigadier-general john hunt morgan, from 1862 to 1863. he joined the 4th regiment alabama cavalry under general joseph wheeler, and served in the battle of chickamauga of 1863. he was captured by union forces and jailed at the camp morton in indianapolis, indiana from october 1863 to february 1865.