History -- Islamic Empire -- Caliphs 8 Biography 5 Caliphs -- 5 History 5 Umayyad dynasty 5 more ... Islam 4 Islam -- 3 Religious aspects -- 3 Abbasids 2 Biography -- 2 Crusades 2 Islamic Empire 2 Kings and rulers 2 Leadership -- 2 Politics and government 2 622-661 1 Arabs -- 1 Assassins (Ismailites) 1 Caliphate 1 Doctrines 1 Environmental law (Islamic law) 1 Environmental protection -- 1 Imams (Shiites) 1 Islamic civilization 1 Islamic stories, Malay 1 Jerusalem -- 1 Kings and rulers -- 1 Muslims -- 1 less ...