This is what he wrote—the following excerpt is translated from Latin by Robert Van Voorst:
[N]either human effort nor the emperor’s generosity nor the placating of
the gods ended the scandalous belief that the fire had been ordered [by
Nero]. Therefore, to put down the rumor, Nero substituted as culprits
and punished in the most unusual ways those hated for their shameful
acts … whom the crowd called “Chrestians.” The founder of this name,
Christ [Christus in Latin], had been executed in the reign of
Tiberius by the procurator Pontius Pilate … Suppressed for a time, the
deadly superstition erupted again not only in Judea, the origin of this
evil, but also in the city [Rome], where all things horrible and
shameful from everywhere come together and become popular.
Tacitus’s terse statement about “Christus” clearly corroborates the New Testament on certain historical details of Jesus’ death.
Tacitus presents four pieces of accurate knowledge about Jesus:
(1) Christus, used by Tacitus to refer to Jesus, was one distinctive way by which some referred to him, even though Tacitus mistakenly took it for a personal name rather than an epithet or title;
(2) this Christus was associated with the beginning of the movement of Christians, whose name originated from his;
(3) he was executed by the Roman governor of Judea; and
(4) the time of his death was during Pontius Pilate’s governorship of Judea, during the reign of Tiberius. (Pilate governed Judea in 26–36 A.D., while Tiberius was emperor 14–37 A.D.)" BiblicalArchaeology
Now in the fifteenth year of the reign of Tiberius Caesar,
Pontius Pilate being governor of Judaea,
and Herod being tetrarch of Galilee,...
Luke 3:1