Sayyīd Muhammad `Abd Allāh al-Hasan (Somali: Sayid Maxamed Cabdille Xasan or Sayyid Mahammad Abdille Hasan), (April 7, 1856, in northern Somalia - December 21, 1920 in Imi, Ogaden) was a Somali religious and nationalist leader. Referred to as the Mad Mullah by the British, he led an armed resistance in Somalia for a period of over 20 years against British, Italian, and Ethiopian forces. The author of this book was Secretary to the Administration, Somaliland, 1916-21.