Robert Alexander, Methodist minister and missionary to Texas, the ninth child of Daniel and Rachael (Moffat) Alexander, was born in Smith County, Tennessee, on August 7, 1811. He joined the Methodist Episcopal Church about 1826. He was admitted into the Tennessee Conference in 1830 and ordained a deacon in 1832 and an elder in 1834. He transferred to the Mississippi Conference in 1835 and in April 1837 was appointed missionary to Texas with Martin Ruter and Littleton Fowler. Alexander, the first of the three to enter the new republic, crossed the Sabine on August 19 and preached his way westward, thus beginning a ministry of forty-five years in Texas. During a camp meeting at the McMahan settlement, he held a "quarterly conference" and formed the San Augustine circuit on September 16. In mid-October he formed the first Methodist missionary society in Texas during a camp meeting held at Caney Creek, southwest of Washington-on-the-Brazos.
When Ruter died in May 1838, Alexander took up Ruter's plans for a college and organized a board of proprietors for Rutersville College. Under Alexander's chairmanship the board raised funds, purchased a site, elected Chauncey Richardson president, obtained a charter and a generous grant of land from the Texas Congress, and opened the school in 1840.
In the meantime, the mission had been organized into the Texas Conference, and Alexander was appointed first presiding elder of the Rutersville District. In the following years he also served as presiding elder of the Galveston, Huntsville, and Chappell Hill districts. His pastoral appointments included Belton, Chappell Hill, Galveston, and Waco. From 1855 to 1858 he was agent for the American Bible Society in Texas.
When the Methodists split over slavery in 1844, Alexander's colleagues elected him delegate to the Louisville Convention that organized the Methodist Episcopal Church, South, in 1845. They subsequently elected him to nine succeeding General Conferences. In 1848 he was instrumental in establishing the Texas Wesleyan Banner, which later became the Texas Christian Advocate (now the United Methodist Reporter), published in Cincinnati, Nashville, New Orleans, New York, and Galveston. After the failure of Rutersville College, Alexander played a prominent role in the effort to establish a central university for Texas Methodism. He was a member of the board of commissioners that located Soule University at Chappell Hill in 1856 and was a trustee there. From 1870 to 1873 he was president of the educational commission that founded Texas University (later Southwestern University) at Georgetown.
Alexander married Eliza Ayres on January 25, 1838. They had a daughter. His wife died on August 30, 1878, and on November 11, 1879, he married Mrs. Patience N. Wilson of Bryan. Alexander died on April 25, 1882, in Chappell Hill, where he was buried. He was later reinterred in Prairie Lea Cemetery in Brenham.