Ellicott's Commentary On The Whole Bible
1 Chronicles 12 - Introduction
XII.
1 Chronicles 12 is a sort of supplement to 1 Chronicles 11, and is throughout peculiar to the Chronicle. It contains two registers: (1) of the warriors who successively went over to David during his outlaw career (1 Samuel 22 ff.), 1 Chronicles 12:1; and (2) of the tribal representatives who crowned David at Hebron (forming an appendix to 1 Chronicles 11:1), 1 Chronicles 12:23.
The first of these registers sub-divides into three smaller lists, viz., 1 Chronicles 12:1.