During the second year that Darius was emperor of Persia, on the first day of the sixth month, the Lord spoke through the prophet Haggai. The message was for the governor of Judah, Zerubbabel son of Shealtiel, and for the High Priest, Joshua son of Jehozadak. 1
References for Haggai 1:1
1.1 Ezra 4.24--5.2; 6.14.