Suetonius

Gaius Suetonius Tranquillus, usually called Suetonius, was a Roman historian who wrote during the early Imperial era; he lived from about AD 69 to some time after AD 122. His most important surviving work is De vita Caesarum, known in English as The Twelve Caesars, a set of biographies of twelve successive Roman rulers running from Julius Caesar to Domitian. He also wrote on the daily life of Rome, on politics and oratory, and on the lives of famous writers, among them poets, historians and grammarians. A few of these other books have partly survived, but many have been lost, so the Twelve Caesars stands as the main record of his work. The Wikipedia lead gives no firm date for his death, and none is claimed here beyond the statement that it fell after AD 122.