A Jewish historian named Jesus's brother James, and scholars accept the passage
Josephus, writing about Judea in the 1st century, mentions the trial of the brother of Jesus called Christ, a man named James. Most scholars accept the line as genuine, not a later Christian insertion. That James went on to lead the first Christian community in Jerusalem, and his exact relationship to Jesus is still debated.
The New Testament names James, Joses, Simon and Judas as brothers of Jesus, along with at least two sisters. What that means divides Christians. Catholics, the Orthodox and some Protestants hold that they were cousins or Joseph's sons by an earlier marriage, a view found in the non-canonical Gospel of James; others take them as children of Mary and Joseph. Catholic tradition also identifies him with James the Less, while almost everyone agrees he is not James son of Zebedee.
Paul knew him personally. On his first visit to Jerusalem he stayed with Peter and says James, the Lord's brother, was the only other apostle he saw. Later he lists James with Peter and John as the three pillars, and names him among those to whom the risen Christ appeared. When Christians in Antioch asked whether Gentile converts had to be circumcised, James spoke last at the Council of Jerusalem; his opinion, dropping that requirement while asking converts to avoid blood and food offered to idols, became the council's ruling.
Historians generally place him at the conservative, law-observant end of early Christianity, in contrast with Paul's emphasis on faith, with scholar James D. G. Dunn casting Peter as the bridge between the two. Admirers called him the Just for his virtue, and Eastern Christians still style him the Brother of God, an epithet used in the oldest surviving Christian liturgy, which bears his name.
Josephus dates his death with some confidence: after the procurator Festus died and before his successor Albinus arrived, the high priest Ananus convened the Sanhedrin and had James condemned to be stoned, which fixes it around 62 AD. The chronicler Hegesippus offers a different account placing it in 69, but most scholars prefer Josephus. Authorship of the Epistle of James, credited to him since 253, is now widely disputed.
Source: James, brother of Jesus