Manassas M. Brown was born on January 23, 1841, in South Carolina to Leonard and Mary Brown. His father was a farmer who owned $6,000 of real estate and $17,500 of personal property by 1860. He lived in Sumter County, South Carolina, and by 1860, he was working as a farm laborer.
He enlisted in the Confederate army on April 12, 1861, and he mustered in as a private in Company D of the 9th South Carolina Infantry. The regiment took part in the siege of Yorktown. Around April 1862, he became a private in Company E of the 1st Palmetto South Carolina Sharpshooters. He was wounded on June 30, 1862, during the Seven Days’ Battles, but he eventually recovered and rejoined the regiment. The Palmetto Sharpshooters took part in the Second Battle of Manassas, the Battle of Antietam, the Overland Campaign, and the Appomattox campaign. He eventually earned a promotion to corporal and then to sergeant. The men surrendered at Appomattox Court House on April 9, 1865, as part of General Robert E. Lee’s Army of Northern Virginia.
Brown returned to Sumter County after the war and resumed his work as a farmer. He married Josephine Lesesne on December 18, 1873, and they had at least four children: Frederick, born around 1874; Leonora, born around 1876; Congers, born around 1878; and Manassas, born around 1879. He died on May 18, 1881.