Al-Mu'ayyad fi'l-DIn al-ShIrzI (d. 470/1087) was an outstanding, multi-talented Fatimid scholar of Persian origin. He excelled as a missionary-agent, statesman, poet, preacher and theologian. Based on his autobiography, this work provides an insight into the remarkable life and achievements of al-Mu'ayyad through important stages of his career, describing his daring attempt to win over the Buyids of western Iran to the Fatimid cause, his dangerous flight to Cairo and finally his expedition to Syria and Iraq to build up an alliance of local rulers against the invading Saljuk Turks.