The books of Haggai and Proto-Zechariah (Zechariah 1-8) belong to the post-exilic books of the Old Testament prophets. The topic of both books is the restitution of Judah and of the Jerusalem Temple. They share a common dating system which refers to the reign of the Persian King Darius I. This study reconstructs the genesis and development of these two prophetic books over a period of several centuries and integrates their various revisions into the historical context of the theology of ancient Judaism.