In the early years of the 20th Century the Ikhwan (brotherhood) movement began to emerge among the beduin. The Ikhwan movement spread Wahhabi Islam among the nomads. Stressing the same strict adherence to religious law that Muhammad ibn Abd al Wahhab had preached, Ikhwan beduin abandoned their traditional way of life in the desert and move to an agricultural settlement called a hijra (pl., hujar). The word hijra was related to the term for the Prophet's emigration from Mecca to Medina in 622, conveying the sense that one who settles in a hijra moves from a place of unbelief to a place of belief. By moving to the hijra the Ikhwan intended to take up a new way of life and dedicate themselves to enforcing a rigid Islamic orthodoxy. Once in the hijra the Ikhwan became extremely militant in enforcing upon themselves what they believed to be correct sunna (custom) of the Prophet, enjoining public prayer, mosque attendance, and gender segregation and condemning music, smoking, alcohol, and technology unknown at the time of the Prophet. They attacked those who refused to conform to Wahhabi interpretations of correct Islamic practice and tried to convert Muslims by force to their version of Wahhabism.