 Complete the following phrase:  The precursor states to Saudi Arabia were Nejd and Hejaz. The state flag of Nejd followed todays Saudi flag pattern very closely. The state of Hejaz followed the patterns seen in countries like Palestine and Sudan. Caliphates such as the Rashiduns, Ummyads, and Abbasids used other flags with only one color. After the Sack of Baghdad in 1258 by the Mongols, the primary caliphate became Mamluk Egypt. In 1517, the Ottomans invaded Egypt and inherited Hejaz and ruled it until the 