Leonidas Lafayette Polk was born in Anson County, North Carolina, on 1837 April 24, the son of farmer Andrew and Serena Autry Polk. Orphaned at age fourteen, Polk spent four years residing with relatives before entering Davidson College in the fall semester of 1855. Within ten months he had taken all available courses in science and agriculture. He returned to Anson County to operate several business ventures and farm family land using slaves inherited from his father. On 1857 September 23, Polk married Sarah Pamela Gaddy, the daughter of an Anson County planter. The Polks had seven children, one son who died in infancy and six daughters.

Polk held several positions in North Carolina government. He was elected to the state legislature in 1860 and 1864, served as a colonel with two North Carolina regiments in the Army of Northern Virginia during the Civil War, and attended the state constitutional convention in 1865. Beginning in the 1870s, Polk began advocating for the creation of a state Department of Agriculture. When such a department was established in 1877, he became its first commissioner, a position he held until 1880.

Polk's lengthy political career was coupled with an extensive career in journalism. In April 1874 he established the weekly , which featured farm and local news and sponsored farmers' clubs. Polk was also the founder and first editor of (1886), which instructed Southern farmers on better agricultural methods. Polk also served as editor of the , which consolidated with the to form the , between 1880 and 1881.

Throughout his career, Polk was interested in North Carolina educational institutions. He organized state farmers to lobby for an agricultural college and joined the Watauga Club in sponsoring legislation that established the North Carolina College of Agriculture and Mechanic Arts, which became North Carolina State University, in 1887. Subsequently, Polk was recruited to assist with the establishment of a Baptist college for women. While a vital participant in this effort, Polk died prior to the 1899 opening of the Baptist Female University, later Meredith College.

Polk also remained interested agriculture during his career. Between 1887 and 1889, Polk was three times elected president of the Interstate Farmers' Association of eleven Southern states. At the 1889 conference, several farmers' organizations consolidated to form the Farmers' Alliance and Industrial Union (National Farmers' Alliance) and elected Polk its President. He was later twice re-elected. Due to his resulting power in national politics, Polk was widely expected to be the presidential nominee of the new People's Party in the 1892 national election. He died, however, on June 11, just months before the party's national convention.