Annas (also Ananus), son of Seth, was a Jewish High Priest from AD 6 to 15 and remained an influential leader afterwards.
Annas was appointed High Priest in AD 6 by the Roman legate Quirinius just after the Romans had deposed Archelaus, Ethnarch of Judaea, thereby putting Judaea directly under Roman rule as part of Iudaea Province. Annas served in the office for ten years, until the procurator Gratus dismissed him in AD 15.
After that, Annas saw several members of his family succeed him as High Priests:
Josephus comments on this situation:
References in the Mosaic Law to "the death of the high priest" (Num 35:25, 28) suggest that the high-priesthood was ordinarily held for life. Perhaps for this reason, Annas was still called "high priest" even after his dismissal, along with Caiaphas (Luke 3:2). He also may have been acting as president of the Sanhedrin, or a coadjutor of the high priest.
According to the Gospel of John (the event is not mentioned in other accounts), Jesus was first brought before Jonathan Ananus, and after a brief questioning of him (John 18:19-23) was sent to Caiaphas, where some members of the Sanhedrin had met, and the first trial of Jesus took place (Matt. 26:57-68).
After Pentecost, he presided over the Sanhedrin before which the Apostles Peter and John were brought (Acts 4:6).