'House of Judah' in the Bible

Then came the men of Judah, and anointed David there, to be king over the house of Judah. And they told David, saying, Men of Jabesh-gilead, were they who buried Saul.

Now, therefore, let your hands be made firm, and become ye sons of valour, for your lord Saul is dead, - and, me, moreover have the house of Judah anointed, to be king over them.

Forty years old, was Ish-bosheth son of Saul, when he began to reign over Israel, and, two years, reigned he, - but, the house of Judah, followed David.

And it came to pass, that, the number of the days that David was king in Hebron, over the house of Judah, was seven years and six months.