After the 1920 Nebi Musa riots, the San Remo conference and the failure of Faisal to establish the Kingdom of Greater Syria, a distinctive form of Palestinian Arab nationalism took root between April and July 1920. With the fall of the Ottoman Empire and the French conquest of Syria, coupled with the British conquest and administration of Palestine, the formerly pan-Syrianist mayor of Jerusalem, Musa Qasim Pasha al-Husayni, said "Now, after the recent events in Damascus, we have to effect a complete change in our plans here. Southern Syria no longer exists. We must defend Palestine".