Jerome Bonaparte (Polly) Robertson, for a time commander of the famed Hood's Texas Brigade, was born in Woodford County, Kentucky, on March 14, 1815, the son of Cornelius and Clarissa Hill (Keech) Robertson. His father, a Scottish immigrant, died in 1819, and in 1823 his mother, almost penniless, apprenticed the eight-year-old Robertson to a hatter who moved in 1824 to St. Louis and took the boy with him. Despite much hardship and privation, Robertson eventually studied medicine at Transylvania University, where he graduated in 1835. As lieutenant in a company of Kentucky volunteers, he offered his services in the Texas Revolution, but the volunteers were delayed in New Orleans and did not arrive in Texas until September 1836. In 1837, having served a year as captain in the Army of the Republic of Texas, Robertson returned to Kentucky and married Mary Elizabeth Cummins, daughter of Moses Cummins. With Mary, her father, his brother James C. Robertson, and his uncle Willet Holmes, he returned to Texas in December 1837 and settled in Washington-on-the-Brazos, where he began his medical practice. Robertson became a respected member of his community and well known as an Indian fighter; he served every year for six years in Indian or Mexican campaigns, including three in 1842-the repulse of the invasions of Adrián Woll and Rafael Vásquez and the retaliatory Somervell expedition. He was coroner of Washington County in 1838–39 and mayor of Washington-on-the-Brazos in 1839–40 and postmaster from 1841 to 1843. He was elected in 1847 to the Texas House of Representatives and in 1849 to the state Senate. He was also a delegate to the Secession Convention in January 1861. He was one of the first Texans to raise a company for Confederate military service; it became part of the Fifth Texas Infantry, Hood's Brigade.
As the fighting intensified, Robertson won rapid promotion. In November 1861 he was made lieutenant colonel and on June 1, 1862, received a commission as a full colonel and was entrusted with the command of the Fifth Texas Infantry. During the Peninsular campaign he fought in the Seven Days battles; at Gaines' Mill the Texas Brigade smashed the Union left. Robertson's troops also played an important part at Second Manassas. Robertson was called "Aunt Polly" by his men because of his concern for their welfare. Months of intense fighting took their toll on him, and at the battle of South Mountain during the 1862 Maryland campaign, Robertson was overcome by exhaustion; he was carried from the field and missed the battle of Antietam. He was promoted to brigadier general on November 1, 1862, and succeeded Hood as commander of the Texas Brigade. He directed this superb unit at Fredericksburg and in the desperate Gettysburg fighting. In September 1863 Robertson and his Texans accompanied Gen. James Longstreet's corps to Tennessee, where the brigade fought with distinction at the battle of Chickamauga. In the course of the disheartening East Tennessee campaign that followed, Robertson incurred the displeasure of Longstreet and division commander Micah Jenkins. Longstreet filed court-martial charges against Robertson, alleging delinquency of duty and accusing him of pessimistic remarks. Robertson was reprimanded, replaced as commander of the Texas Brigade, and transferred to Texas, where he commanded the state reserve forces until the end of the war.
After the surrender Robertson returned to his home in Independence and practiced medicine until 1874, when he became superintendent of the state bureau of immigration. He served as passenger and emigration agent for the Houston and Texas Central Railroad in 1876. Three years later he moved to Waco, where he continued to promote West Texas railroad construction. He and his wife, Mary, had three children, one of whom died in infancy. His son Felix Huston Robertson was a brigadier general in the Confederate Army. Mary died in 1868, and in 1878 Robertson married Mrs. Hattie Hendley Hook. He held high Masonic offices, including deputy grand master of the Third Masonic District and of the Twenty-ninth Masonic District. He was an organizer of the Hood's Texas Brigade Association, which he served as president several times. He died on January 7, 1890, and was buried at Independence next to his first wife and his mother. In 1894 his son had all three bodies moved to Oakwood Cemetery in Waco.