Answer
Gordian III's maternal grandfather was Gordian I, a Roman emperor who reigned briefly in 238 AD. Gordian III's mother, Tranquillina, was the daughter of Gordian I and his wife Fabia Orestilla. Gordian I was a wealthy and influential senator who had been appointed governor of Africa by the emperor Maximinus Thrax. When Maximinus was overthrown, Gordian I was proclaimed emperor by the African legions.