After serving as a plebeian tribune, Marcellinus appears in the historical record as a legate of Pompey in 67 BC.
[2] After his praetorship, Marcellinus was appointed governor of Syria for the term 59/58 BC.
[3] Around 55 BC he issued denarii celebrating his famous ancestor, Marcus Claudius Marcellus.
[4] By his first wife he was the father of Lentulus Marcellinus, Caesar's quaestor put in command of his fortifications at Dyrrhachium in 48 BC.
[6] Some authorities, such as Ronald Syme, believed Cornelius Marcellinus died young;[7] however, John Scheid has persuasively argued that he should be identified with Publius Cornelius Lentulus Marcellinus, consul of 18 BC.