Platted in 1906, the Gaines County seat experienced an oil boom and was incorporated in the 1930s. The County extensively remodeled and added to the 1922 courthouse, now a 1955 Modern building of concrete and limestone. Seminole’s Gaines County Museum preserves colorful county history through locally donated artifacts and photographs. Interesting items include a large typewriter collection, a combination dentist-barber chair and a barbed wire collection. One photograph tells the story of Seminole’s three Sullivan brothers who served together during World War II. Unsuccessful efforts were made to split them up, but all three survived.