Question: Which Roman emperor was personally known by or written about by both Thrasyllus of Mendes and Tacitus?
Sentence (from "Thrasyllus of Mendes"): Thrasyllus was an astrologer and a personal friend of the Roman emperor Tiberius, as mentioned in the "Annals" by Tacitus and "The Twelve Caesars" by Suetonius.
Relevant evidence: Yes