There were three early popes who were supposedly from Africa: Victor I, pope from 189 to 199, Meltiades (or Melchiades), reigned 311-314, and Gelasius I, reigned 492-496. There is no evidence that they were black Africans...probably they were from the Roman province of Africa (roughly modern Tunisia).
Gelasius I is characterized as natione Afer (an African by nation) but also as Romanus natus (Roman born).
Pope St. Melchiades may be Mel Martinez's patron saint.