Complex sentence: Didius Marinus was a powerful Roman noble of Equestrian order who served as Procurator in various provinces throughout the Roman Empire, who later became a tax collector and Tribune of the first Praetorian cohort.
Split into simpler sentences: Didius Marinus was a powerful Roman noble of equestrian rank who served as Procurator in various provinces. He later became a tax collector and tribune of the first Praetorian cohort.