Thomas Bentley Mott was born in 1865 to Dr. Armistead Randolph (1822-1894) and Virginia Bentley (ca. 1825- 1905) Mott in Leesburg, Virginia. He had six siblings - Mary (ca. 1848- 1926), Roberta (ca. 1853-?), Virginia (ca. 1855-?), Armistead Randolph Jr. (ca. 1858- 1889), Kate (ca. 1859-?), and Eleanor (1861-1937). Mott attended public schools until age 11, when his parents placed him in a small private school operated by Anne Harriotte (Mrs. Matthew) Harrison (1822-1894). In 1882 he enrolled at West Point, graduating in 1886. After serving in the army and attending artillery school, Mott returned to West Point as a teacher around 1890. In 1895 he joined the staff of General Wesley Merritt (1834-1910) as his aide-de-camp, and served under him in the invasion of Manila during the Spanish-American War in 1898.

Mott was appointed United States military attaché in Paris in 1900, a position he held for 20 years including 10 years with Ambassador Myron T. Herrick (1854-1929). He retired from the army in 1914, but asked to be recalled to active service when the United States entered World War I. Mott returned to France with General John J. Pershing (1860-1948), whom he represented on the staff of Marshal Ferdinand Foch (1851-1929). After the end of the war the French awarded Mott the ribbon of a Commandeur de la Legion d'Honneur.

On 23 May 1923, Mott married Rose Gabrille Georgette Saint Paul (1891-1943), daughter of M. and Mme. Georges Saint Paul (n.d.) in Paris. Born in St. Germain en Laye in France, little information is available about her early life. During World War I she became a heroine to the French for her work outfitting and running a mobile hospital. She was awarded the Chevalier de la Legion d'Honneur, Croix de Guerre, and the American Order of Merit.

During World War II, the Motts lived in Biarritz, France. Georgette Mott founded the Aid for the Cote Basque, a relief agency to feed hungry French children. T. Bentley Mott served as head of the American Fund for the French Wounded. At the end of his army career, Mott turned to writing and published several books, including a memoir, . He died in Biarritz 17 December 1952. Georgette Mott died on 26 January 1943 in Cannes, France.