Nahash

And it came to pass after this, that the king of the children of Ammon died, and Hanun his son reigned in his stead.

Then said David, I will shew kindness unto Hanun the son of Nahash, as his father shewed kindness unto me. And David sent to comfort him by the hand of his servants for his father. And David's servants came into the land of the children of Ammon.

And Absalom made Amasa captain of the host instead of Joab: which Amasa was a man's son, whose name was Ithra an Israelite, that went in to Abigail the daughter of Nahash, sister to Zeruiah Joab's mother.