Mesopotamia, Persia and Kuwait in-between the wars

Before WW1, what was to become Iraq was administered as three provinces of the Ottoman or Turkish Empire, none of which identified strongly with the others: Mosul, Baghdad and Basra, collectively known as Mesopotamia. Persia (today’s Iran), had been a British protectorate since 1899, as was Kuwait. All three states have become important in recent history. So what was British rule like in those inter-war years?