What is this between the Sunnis and Shias?

Watch this video done on the Shia-Sunni historical split by Lesley Hazleton an agnostic Jew. Her book is well respected and found here.

Although some parts of this video are historically wrong or controversial, it provides an interesting description of some aspects of Shia and Sunni from a Jewish perspective. For example, all Imam Hussain’s companions died at the day of Ashura (10th day) from morning to around noon, whereas based on the video, most companions die before Ashura and then at the Ashura, Imam Hussain dies.