A persistent difficulty surrounds James the Just: the New Testament knows more than one James, and the traditions have often merged them. Besides James the brother of the Lord, the twelve apostles included James son of Zebedee (James the Greater) and James son of Alphaeus, and Mark mentions a James the Less. A long Western tradition, following Jerome, identified James the Just with James son of Alphaeus so as to keep him among the Twelve and to protect the doctrine that Jesus had no true brothers; the Eastern churches generally kept the brother of the Lord distinct from the apostle. The atlas treats James the Just on his own page precisely to avoid that conflation.
His name was also attached to the Epistle of James in the New Testament, whose author calls himself simply "James, a servant of God." Tradition ascribed it to the brother of the Lord, and its strong ethical and Jewish-Christian character fits that setting; many modern scholars, however, note its polished Greek and later concerns and treat the attribution as uncertain.
In the end the securely historical James is the one the earliest sources agree on: the brother of Jesus, leader of the Jerusalem church, and martyr of about 62 CE, a figure who stands, more firmly than most, on the joint testimony of Paul, Acts and Josephus.