1 Kings 16:23-24

Omri became king of Israel during the thirty-first year Asa was king of Judah. Omri ruled Israel for twelve years, six of those years in the city of Tirzah. He bought the hill of Samaria from Shemer for about one hundred fifty pounds of silver. Omri built a city on that hill and called it Samaria after the name of its earlier owner, Shemer.