Berrien McPherson Zettler was born around 1842 in Effingham County, Georgia, to Nathaniel Zettler. His father was a farmer who owned $2,000 of real estate and $16,300 of personal property by 1860. His father also enslaved at least 39 people. Zettler grew up and attended school in Effingham County before enrolling at Newberry College in 1859. He left school in January 1861 after Georgia seceded from the Union.
Zettler received a commission as a lieutenant in the Georgia militia. Soon afterward, on May 21, 1861, he mustered into Confederate service as a private in Company B of the 8th Georgia Infantry. The regiment took part in the First Battle of Manassas, the Seven Days’ Battles, and the Second Battle of Manassas. He was wounded in the left thigh in the Second Battle of Manassas on August 30, 1862, and Confederate officials assigned him to the Quartermaster’s Department in Savannah, Georgia. He remained in the army until at least October 1864.
Zettler returned to Effingham County, and he married Harriet F. Eaton on January 2, 1868. She may have died soon afterwards, and he married Harriet M. Guyton on May 19, 1870. They had at least three children: Guyton, born around 1873; Gordon, born around 1874; and Hattie, born around 1878. They lived in Macon, Georgia, and Zettler worked as a public school superintendent. His wife died on December 20, 1887, and he married Mahuldah Harris in January 1890. They lived in Atlanta, Georgia, and Zettler worked as an insurer. He eventually returned to teaching, and he ran for state school superintendent as a Democrat in 1912. He died in Atlanta on March 31, 1915.