Belvoir was established as a coton plantaion in 1825 by Reuben Saffold II. Saffold was born on September 4, 1788 in Wilkes County, Georgia. He was educated there and began a law practice in Watkinsville, Georgia. He married Mary Evelyn Phillips, of Morgan County, in 1811. The couple would eventually have 12 children together. They relocated to Clarke County, Mississippi Territory in 1813, where he participated in the Creek War in 1813-14. Saffold served in the legislature of the Alabama Territory in 1818. He participated in the Constitutional Convention and became an Alabama circuit judge in 1819. He established his plantation, which he named Belvoir, in rural Dallas County, Alabama in 1825. Belvoir translates roughly from French to English as "beautiful to see." He remained a circuit judge until 1832, when he was appointed to the Alabama Supreme Court. He served as Chief Justice from 1834 until 1836.
Although the plantation at Belvoir was established in 1825, the construction date for the current main house is unclear. It is known that the Saffolds were still living in a large hewn log house in 1838, when Englishnaturalist, Philip Henry Gosse, was serving as a teacher for the Saffolds and other area children. Some of his experiences at Belvoir, including his negative impressions of slavery, were later published in his book, Letters from Alabama: Chiefly Relating to Natural History. Family records indicate that the current main house was built prior to the death of Saffold on February 15, 1847. Architectural historians usually date it to the early to mid-1850s, due to stylistic elements found in its architecture.