Martin

Martin, the name of five Popes: M. I., St., Pope from 649 to 655; M. II., Pope from 882 to 884; M. III., Pope from 942 to 946; M. IV., Pope from 1281 to 1285; M. V., Pope from 1417 to 1431, distinguished for having condemned Huss to be burned.

Definition taken from The Nuttall Encyclopædia, edited by the Reverend James Wood (1907)