'League' in the Bible

Then Abner sent messengers to David [who was] in his place [at Hebron], saying, “Whose is the land? Make your covenant (treaty) with me, and behold, my hand shall be with you to bring all Israel over to you.”

David said, “Good! I will make a covenant (treaty) with you, but I require one thing of you: you shall not see my face unless you first bring Michal, Saul’s daughter, when you come to see me.”

Abner said to David, “Let me stand up and go, and gather all Israel to my lord the king, so that they may make a covenant (treaty) with you, and that you may reign over all that your soul desires.” So David sent Abner away, and he went in peace.