'Assalaam Alaikum,
Here's the continuation of Fatimi History from the book
Speaking Among Friends
"For this purpose he (the 20th Imaam) directed his grand emissary in Yemen, to establish the institution of the vicegenerent of the Imam which dignitary was to function as the sole deputy of the Imams in seclusion, exercising all their powers to the fullest extent. The vicegerent came to be known as Dai-el-Mutlaq and his office necessitates the unfailing discharge of the two obligations, viz., that the Dai-el-Mutlaq would take care to appoint a successor in time and that he would always carry on his mission in the name of the Imams with all the authority and power inherent in that high office.
When the 21st Imam went into seclusion in 1132 A.D., on the authority of the Imam, the institution of Dai-el-Mutlaq was established, which continues vigorously without interruption to this day. The first to enter upon the august office in Yemen was Syedna Zoeb. In all 23 Dai-el-Mutlaqs functioned in Yemen before the seat of authority was shifted to India.
From Yemen, after a preparatory period lasting well-nigh two centuries, the seat of Dawat was transferred to India. Already ties of friendly intercourse, exchange of thought and culture and trade had existed for long between India and Yemen. The followers of the Dai in Yemen had settled down in India, and the more eminent amongst them used to visit Yemen, would stay with the Dais for long periods, acquire first-hand knowledge of the traditions of the faith and also observe how the Dais were managing the affairs of the community. The Dais also had representatives on the Indian soil to attend to the needs of their followers. When extreme persecution of the Fatimi followers on the ground of differing beliefs and adherence to the successive Fatimi Imams and Dais led to a sense of insecurity, the Dais chose India for the transfer of the Dawat in the knowledge and belief that this country was receptive and tolerant towards varying faiths and creeds. The first Dai to hold office in India was Syedna Yusuf Najmuddin in the year 1539 A.D. He commenced his mission in Gujarat and gradually the followers spread to other parts of India..."
Abde Syedna (TUS)
Wa'salaam,
Huzefa