II Chronicles 11: All The Tribes?

People are fond of talking about "the ten lost tribes" of Israel, as if every trace of their bloodlines have been lost forever.  But II Chronicles 11 reveals that many came to Judah from the northern kingdom to support Rehoboam's reign, thus continuing their representation in the southern kingdom.  In addition to the Levites, who left their property in the north to come to Judah, we read, "Those who had set their hearts to seek the Lord God of Israel came after them from all the tribes of Israel to Jerusalem to sacrifice to the Lord, the God of their ancestors" (vs. 16).  This brings up another point about II Chronicles from here on out: unlike I and II Kings, this book focuses exclusively on the southern kingdom of Judah and David's descendants.