Rukhsar Parveen asked 5 years ago

I am currently in my first year studying at Notre Dame sixth form and am doing the Extended Project Qualification which is a 5000 word dissertation on a subject of my choice. I have decided to write about the divide within Islam between the Shia and Sunni Muslims. I am very interested in the topic and I was hoping you could help me by telling me what you think was the main cause for the split. I hope you can help and fully understand if you do not wish to.
Thank you