John H. Reagan, for whom the county was named, was a Texas Confederate born in 1818 and died in 1905. He was a delegate to the Texas Secession Convention and, while a member of the 1st Confederate Congress, was made postmaster general of the C.S.A. in 1861. He began that difficult job after a raid on the U.S. Postal Department for southern personnel asking them to get maps and forms. Despite seizure of mail by the enemy, the army draft of clerks and carriers, and the split of the South, the department carried on. At the war's end he was imprisoned in Boston. He later served as a U.S. Senator and as the first chairman of the Railroad Commission.