The major cause for the division of Islam was disagreement over?

Explanation:

They chose sides following the death of the Islamic prophet Muhammad in AD 632. A dispute over succession to Islamic prophet Muhammad as a caliph of the Islamic community spread across various parts of the world, which led to the Battle of Jamal and Battle of Siffin.

There are three traditional types of schools in Islam: schools of jurisprudence, Sufi orders and schools of theology. Other types of Islamic denominations and movements have arisen in the modern era.

it increased the power of the king of england.