Late in the third millennium B.C., waves of invaders speaking Indo-European languages crossed the Caucasus Mountains into Anatolia. Building on other older cultures, these invaders borrowed even their name, the Hittites, from the indigenous Hatti whom they had subjugated. The Hittites were supposed to have entered Cappadocia around 1800 B.C. The Hittite empire with its capital at Bogazkoy (also called as Hattusas), was the chief power and cultural force in Western Asia from 1400 to 1200 B.C. It was a loose confederation that broke up under the invasions (c.1200 B.C.) of the Thracians, Phrygians, and Assyrians. The Neo-Hittite kingdom (c.1050-c.700 B.C.) that followed was conquered by the Assyrians. The Hittites were one of the first peoples who could smelt iron successfully. The Hittites spoke an Indo-European language.