The study deals with the definition of the fortress of Kiva (in terms of geographical location, and the most famous scientists from the fifth century to the eighth century of the eleventh / eleventh century to the fourteenth century. The research deals with the scientists of the fortress of Kiva and their contributions to the prosperity of various science and scientific knowledge through research in the conduct of their scientists, We have mentioned a brief account of the scholars who were born in it or those who came to it and settled in it and resided, relying on the year and the death of each of them without dividing the type of science which excelled in it. The reason for this is due to their mastery of several sciences in one, and this is characteristic of Arab and Muslim scholars in general of scientific encyclopedias. Unfortunately, we have mentioned in their biography a mention of their names, some of what was known about their lives, the sciences in which they were created and their various works, which played an important role in promoting different aspects of knowledge which we get from different sources. We found only the simple references to some biographies around us.