Following World War I and the dissolution of the Ottoman Empire, and the subsequent dissolution of the Caliphate by Mustafa Kemal Ataturk (founder of Turkey), many Muslims perceived that the political power of their religion was in retreat. There was also concern that Western ideas and influence were spreading throughout Muslim societies. This led to considerable resentment of the influence of the European powers.  Islam has exercised considerable political and social influence throughout its history. Early rulers in the Middle East and elsewhere claimed legitimacy for their authority in the name of Islam, and Islamic teachings gave structure to almost every facet of society. But these early Muslim states and empires were not theocracies that is, governments ruled by religious leaders or clergy until the creation of the Islamic Republic of Iran in 1979.