You need to go back to history 101. You didn't distinguish in your question between Arab Islamic empire and the Islamic Ottoman Empire. You stated," Moslem Empire and the Ottoman Empire". Moslem is Islam. Islam is Moslem. Moreover, the pure Arab ISlamic empire only lasted approx 100 years - the Umayyads. Then the caliphate moved and became the Abbasids which many consider to be the supplanting of the semitism of Arabia with the aryanism of the Perisians. Maybe if you understood the differences you could ask questions which made sense.
Don't blame your reading comprehension problems on me.