All Israel came together to David at Hebron and said, "Here we are, your own flesh and blood.
References for 1 Chronicles 11:1
Even when Saul was king, you led us out [to battle] and brought us back. The Lord your God also said to you, 'You will shepherd My people Israel and be ruler over My people Israel.' "
So all the elders of Israel came to the king at Hebron. David made a covenant with them at Hebron in the Lord's presence, and they anointed David king over Israel, in keeping with the Lord's word through Samuel.
References for 1 Chronicles 11:3
David and all Israel marched to Jerusalem (that is, Jebus); the Jebusites who inhabited the land were there.
References for 1 Chronicles 11:4