By 1827 he had formed a partnership with William Plunkett Harris to operate steamboats along the Mississippi and Red rivers. Within a year Wilson had joined his partner's Texas brother, John Richardson Harris, in developing Harrisburg. By the time John Harris died in 1829 from yellow fever, Wilson was living in Harrisburg, where he owned a gristmill and sawmill. He was later accused by Harris's widow of fraudulently claiming much of her late husband's business as his own. Before her suit was settled in 1838, promoters Augustus C. and John K. Allen had dropped plans to develop their new city of Houston on this disputed site.
Wilson married wealthy New Orleans widow Sarah Reed in 1830. At some point he built two customhouses for the Mexican government, at Galveston and Velasco. In 1832 he joined fellow Texans in laying siege to the garrison at Anahuac. Wilson subsequently provided two ships to transport the Mexican troops at Anahuac back to Mexico. In 1832 and 1833 he was elected a delegate to conventions in San Felipe that considered Texas grievances. Wilson volunteered for the army in 1835 and became a colonel. After participating in the siege of Bexar in November, he left for New Orleans to raise money and volunteers. When he returned in May 1836, after the San Jacinto victory, he found that his entire livelihood at Harrisburg had been burned by the Mexican army.
Wilson was elected to the Texas Senate in 1836 and served a three year term. He became associated with the Allen brothers in developing Houston and also promoted the town of Hamilton (which merged with Harrisburg in 1839) and a railroad. In 1838 he was a candidate (apparently self-announced) for president, but he received only 252 votes against Mirabeau B. Lamar's 6,995. In 1844 Wilson again quixotically ran for president but was ignored. The next year he was defeated for a delegate position to the convention that approved annexation. For the last ten years of his life he avoided politics and focused on the real estate business. His more successful son James Theodore Wilson twice served as mayor of Houston after the Civil War. Robert Wilson died on May 25, 1856, and was buried in a family cemetery in Houston. His remains were later moved to Glenwood Cemetery.
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