Some flags of Muslim states use inscribed flags, either with the shahada, as in the flags of Saudi Arabia, or in the case of the 1979 Islamic Republic of Iran, stylized writing of the word Allah. The flag of Iraq uses the pan-Arab colours since 1921, with the addition of the takbir since 1991. The practice of inscribing the shahada on flags may go back the 18th century, used by the Wahhabi religious movement.[30] In 1902 Ibn Saud, leader of the House of Saud and the future founder of the Kingdom of Saudi Arabia, added a sword to this flag.[30] The current flag of Saudi Arabia is a continuation of the flag Emirate of Nejd and Hasa introduced in 1902.