CALENBERG, or Kalenberg, a former principality of Hanover, which was traversed by the Weser and the Leine, and had an area of about 1050 square miles. It derived its name from an ancient castle, now in ruins. In the Middle Ages it belonged to Lüneburg, and after passing from one branch to another of the house of Brunswick, it came, in 1705, to Ernst August, electoral prince of Hanover.