chief. heads: i.e. heads of houses.
them that went up. Most of these names appear in Ezr. and Nehemiah 10. The number is 1,496. If there were no women with them, this might be the cause of the "strange" marriages in Ezra 1. and Nehemiah 10.
Artaxerxes: i.e. Darius (Hystaspis). See App-57 and App-58.