Thompson was a politician and diplomat. He was born in South Carolina in 1798 and attended South Carolina College where he studied law. He practiced law in Greenville, SC, and served as a state legislator and later US Representative, where he advocated for the recognition and annexation of Texas. After the Texas Santa Fe Expedition failed and most members imprisoned in Mexico, Thompson was named a minister plenipotentiary to Mexico to demand the release of the prisoners, many of whom were US citizens. He secured the release of 300 prisoners. He retired from politics over his disapproval of the Mexican War and died in Florida in 1868.