Death of Denethor (4997 F.A.) - In the First Battle of Beleriand, Denethor, king of the Nandor, was killed.

"Denethor was cut off and surrounded on the hill of Amon Ereb.  There he fell and all his nearest kin about him, before the host of Thingol could come to his aid.  Bitterly though his fall was avenged, when Thingol came upon the rear of the Orcs and slew them in heaps, his people lemented him ever after and took no king again." ~The Silmarillion, chap. 10 (Of the Sindar)