1:1 The Lord spoke to Moses in the wilderness of Sinai, in the tent of meeting, on the first day of the second month, in the second year after they had come out of the land of Egypt, saying, 2 “Take a census of all the congregation of the people of Israel, by clans, by fathers' houses, according to the number of names, every male, head by head. 3 From twenty years old and upward, all in Israel who are able to go to war, you and Aaron shall list them, company by company. 4 And there shall be with you a man from each tribe, each man being the head of the house of his fathers. 5 And these are the names of the men who shall assist you. From Reuben, Elizur the son of Shedeur; 6 from Simeon, Shelumiel the son of Zurishaddai; 7 from Judah, Nahshon the son of Amminadab; 8 from Issachar, Nethanel the son of Zuar; 9 from Zebulun, Eliab the son of Helon; 10 from the sons of Joseph, from Ephraim, Elishama the son of Ammihud, and from Manasseh, Gamaliel the son of Pedahzur; 11 from Benjamin, Abidan the son of Gideoni; 12 from Dan, Ahiezer the son of Ammishaddai; 13 from Asher, Pagiel the son of Ochran; 14 from Gad, Eliasaph the son of Deuel; 15 from Naphtali, Ahira the son of Enan.” 16 These were the ones chosen from the congregation, the chiefs of their ancestral tribes, the heads of the clans of Israel.
17 Moses and Aaron took these men who had been named, 18 and on the first day of the second month, they assembled the whole congregation together, who registered themselves by clans, by fathers' houses, according to the number of names from twenty years old and upward, head by head, 19 as the Lord commanded Moses. So he listed them in the wilderness of Sinai. (ESV)