And of the children of Issachar, which were men that had understanding of the times, to know what Israel ought to do; the heads of them were two hundred; and all their brethren were at their commandment. (1 Chronicles 12:32)
These men of Issachar were men who had wisdom to understand the meaning of current events and who were able to provide intelligent counsel (see Esther 1:13). They evidently saw that David was the man of the hour, and that it was prudent for Israel to accept him.