A city built of white stone, Amman's growth has skyrocketed since it was made the capital of Trans-Jordan in the early 1920s, but especially after the 1948 and 1967 wars with Israel when hundreds of thousands of Palestinian refugees settled. Another wave arrived after the second Iraq war, with Iraqi refugees forming the majority of newcomers. Its history, however, goes back many millennia. The settlement mentioned in the Bible as Rabbath Ammon was the capital of the Ammonites, which later fell to the Assyrians. It was dominated briefly by the Nabataeans before it became a great Roman trade center and was renamed Philadelphia. After the Islamic conquests, Amman became part of the Muslim empire, until the Ottomans were forced out by the Allies, with the help of the Hashimites, who formed a monarchy that continues to rule until the present.