Lydia (Lydian: ‎𐤮𐤱𐤠𐤭𐤣𐤠, Śfarda; Aramaic: Lydia; Greek: Λυδία, Lȳdíā; Turkish: Lidya) was an Iron Age kingdom of western Asia Minor located generally east of ancient Ionia in the modern western Turkish provinces of Uşak, Manisa and inland Izmir. The ethnic group inhabiting this kingdom are known as the Lydians, and their language, known as Lydian, was a member of the Anatolian branch of the Indo-European language family. The capital of Lydia was Sardis. The Kingdom of Lydia existed from about 1200 BC to 546 BC. At its greatest extent, during the 7th century BC, it covered all of western Anatolia. In 546 BC, it became a province of the Achaemenid Persian Empire, known as the satrapy of Lydia or Sparda in Old Persian. In 133 BC, it became part of the Roman province of Asia. Lydian coins, made of silver, are among the oldest coins in existence, dated to around the 7th century BC.