Persian sources in Islamic history

The eighth century AH in Iran was distinguished by a group of contemporary historical encyclopedias that distinguished it, along with the century immediately following it, as the era of writing history in Iran. As for the historical works that preceded these two centuries, they were few and far between, and most of them were of the type of "special history," that is, relating to one of the statelets. , or in a town in a country, and there are many "special" or "local" histories that arose in different eras.
When the eighth century began, the general history of Iran began to be written in the Persian language, and a number of reliable historical encyclopedias appeared, which became the mainstay in the study of the history of Iran in particular, and also became one of the most important references for the study of Islamic history in general.
It is on these two types of history books (special and general) that the researcher must rely in his study of Islamic and Iranian history. General history books benefit him in terms of linking events and coordinating historical facts. Special history books also provide him with information and details that general history books may not be interested in due to their broad scope and large number. Topics you cover.