There are a number of uncertainties and disputed issues in the early history of Islam.
[a] Most of these disputes can be traced to Shi'a-Sunni disagreements.
Shi'a often argue that history has been distorted to further a Banu Umayyad agenda.
[4] In many cases, complications with the historiography of early Islam have also resulted in lack of consensus within denominations of Islam.
The uncertainties include: