There were about eleven dialects in Old French, but not all were of literary importance, and all were increasingly dominated from the end of the twelfth century by Francien, the language used by the royal court and the centralized administration in and around Paris.
Source: wiktionary
The scarcity of texts localizable to the Ile-de-France region would seem to pose a serious challenge to Francien's privileged status.
Source: wiktionary
Conversely, native Francien-speaking poets often displayed a degree of linguistic smugness and superiority.
Source: wiktionary
Grammars of Old French are without exception based on the Francien dialect.
Source: wiktionary