It is clear that historical sources such as chronicles etc. represent the starting point in any historical analysis in the field of Islamic studies. Apart from these sources, however, in this study the advantages of prosopographical literature are boldly used while the risks are not ignored. In contrast to Byzantine hagiographical or biographical works in other cultures, Arabic prosopographical literature is abundantly available, representing a tempting source for gaining insights into the social structures of Islam. Not all Islamists recognize the importance of this genre because it is no doubt tendentious. Most of the early biographical works primarily deal with traditionists while members of other parts of the Islamic society are neglected. Apart from this lack of representativeness, some reports are obviously manipulated and not infrequently persons are credited with opinions that they in fact didn't profess or unpleasant doctrines that they held were deliberately suppressed. Nevertheless, the portion of true details in the reports renders them an indispensable historical source. What is incumbent on the historian is the difficult task of separating the chaff from the wheat.