'House of Judah' in the Bible

When Rehoboam had come to Jerusalem, he assembled the house of Judah and Benjamin, one hundred eighty thousand chosen men, who were warriors, to fight against Israel, to bring the kingdom again to Rehoboam.

Behold, Amariah the chief priest is over you in all matters of the LORD; and Zebadiah the son of Ishmael, the ruler of the house of Judah, in all the king's matters: also the Levites shall be officers before you. Deal courageously, and may the LORD be with the good."

Now when Athaliah the mother of Ahaziah saw that her son was dead, she arose and destroyed all the royal family of the house of Judah.