Mary Boykin Miller was born on March 31, 1823, on her grandparents' plantation, near Stateburg, South Carolina, in the High Hills of Santee. Her parents were Mary Boykin (1804–85) and Stephen Decatur Miller (1788–1838), who had served as a U.S. Representative. In 1829 he was elected governor of South Carolina and in 1831 a U.S. Senator.

Miller was educated in Charleston at Mme. Talvande's French School for Young Ladies, reflecting the city's French Huguenot heritage and social aspirations. Miller became fluent in French and German, and received a strong education.

After many years’ courtship, Mary Boykin Miller married James Chesnut, Jr. (1815–85) on April 23, 1840. He was a lawyer and politician eight years her senior. He later became a U.S. Senator from South Carolina. He served in the Senate from 1858 until South Carolina's secession from the Union in 1860. Once the Civil War broke out, James Chesnut, Jr. became an aide to President Jefferson Davis and was commissioned a brigadier general in the Confederate Army.

Mary Chesnut was intelligent and witty, actively taking part in her husband’s career. The Chesnuts’ marriage was at times stormy due to difference in temperament (she was more hot tempered and sometimes considered her husband reserved). Nevertheless their companionship was mostly warm and affectionate. They had no children.

As Mary Chesnut described in detail in her diary, the Chesnuts had a wide circle of friends in the upper society of the South and government of the Confederacy. Among their friends were, for example, Confederate general John Bell Hood, politician John L. Manning, general and politician John S. Preston and his wife Caroline, general and politician Wade Hampton III, politician Clement C. Clay and his wife Virginia, and general and politician Louis T. Wigfall and his wife Charlotte. The Chesnuts were also family friends of Confederate President Jefferson Davis and his wife Varina Howell.

Mary Boykin Chesnut died at her home, Sarsfield, in Camden, South Carolina in 1886 and was buried next to her husband in Knights Hill Cemetery in Camden, South Carolina.

Mary Boykin Chesnut began her diary on February 18, 1861, and ended it on June 26, 1865. She was an eyewitness to many historic events as she accompanied her husband to significant sites of the Civil War. Among them were Montgomery, Alabama and Richmond, Virginia, where the Provisional Congress of the Confederate States of America convened; Charleston, where she was among witnesses of the first shots of the Civil War; Columbia, South Carolina, where her husband served as the Chief of the Department of the Military of South Carolina and brigadier general in command of South Carolina reserve forces; and again Richmond, where her husband served as an aide to the president. At times they also lived with her parents-in-law in a house called Mulberry Plantation near Camden. While it was relatively isolated in thousands of acres of plantation and woodland, they entertained many visitors.

The diary was filled with the cycle of changing fortunes during the Civil War. Although she edited it during the 1870s and 1880s for publication, she retained the sense of events unfolding without foreknowledge. She was very politically aware, and analyzed the changing fortunes of the South and its various classes through the years. She also portrayed southern society and the mixed roles of men and women. She was forthright about complex and fraught situations related to slavery, particularly the abuses of sexuality and power. For instance, Chesnut confronted the problem of white men fathering children with enslaved women in their own extended households.

Chesnut explicitly worked to create literature; she described people in penetrating and enlivening terms. Literary scholars have called the Chesnut diary the most important work by a Confederate author. Chesnut captured the growing difficulties of all classes of the Confederacy.

Because Chesnut had no children, before her death she gave her diary to her closest friend Isabella D. Martin and urged her to have it published. The diary was first published in 1905 as a heavily edited and abridged edition. Later versions have retained more of her original work, and have been annotated to fully identify the large cast of characters.

Publication history

• 1905: A Diary from Dixie

• 1949: An expanded edition, edited by Ben Ames Williams and annotated to identify the people and places

• 1981: A new edition entitled Mary Chesnut's Civil War, edited by historian C. Vann Woodward

• 1982, Mary Chesnut's Civil War, edited by C. Vann Woodward, won a Pulitzer Prize.

• Ken Burns used extensive readings from Chesnut's diary in his documentary television series, The Civil War. Academy Award-nominated actress Julie Harris read these sections.

• In 2000, Mulberry Plantation, the house of James and Mary Boykin Chesnut in Camden, South Carolina, was designated a National Historic Landmark, the highest honor for a site, due to its importance to America's national heritage and literature. The plantation was where Mary Boykin Chesnut resided when she wrote most of her diary. The plantation and its buildings are representative of James and Mary Chesnut's elite social and political class.