Benjamin M. Baker, the seventh of ten children of Benjamin H. and Eliza (Greer) Baker, was born on January 20, 1850, in Russell County, Alabama. His father was a member of the Alabama Secession Convention in 1861 and fought for the Confederacy as a lieutenant colonel of the Sixth Alabama Infantry. Baker received no formal education. He moved to Carthage, Texas, at the age of nineteen and studied law in the office of A. W. Deberry. He was admitted to the bar in 1871 and began his practice at Carthage, where he married Emily Hull in 1872. They had three daughters and a son, who died at the age of six.
Baker represented Rusk, Panola, and Shelby counties in the Fifteenth, Sixteenth, and Seventeenth legislatures at Austin. In the Seventeenth Legislature he chaired the committee on finance and, in the Eighteenth, the committee on penitentiaries. In January 1883, after practicing law for a short time in Decatur, he became secretary of the State Board of Education, which appointed him first state superintendent of education. He was elected to that office in 1884 and served until 1887, when he moved his family to the new rail town of Canadian, in the Panhandle. There he resumed his private law practice and in 1891, with John Pugh, founded the Canadian Enterprise, which under later owners merged with the Canadian Record. In 1890 Baker was elected judge of the Thirty-fifth Judicial District, and he served in that position until 1917, when he retired to his private practice. He died at Canadian on May 21, 1918, and is buried there. B. M. Baker School in Canadian is named for him.