This is the lower-right sheet only of a six-sheet wall map oft he Ottoman Empire printed in Istanbul in 1901, drafted by group of army officers led by Major Omar Enver.
The present map sheet depicts much of Hejaz, including Mecca, Medina and Jeddah, as well as all of Asir and most of Yemen including Sana’a and Aden. It also embraces the southern part of the Red Sea, including the adjacent African coast, with parts of Eritrea, Ethiopia, Sudan, Egypt and Djibouti.
The map was made during a period when the Ottomans were, with great difficulty, attempting to assert their authority in the Yemen and Asir. The Sublime Porte’s control over the holy cities of Mecca and Medina was central to the Sultan’s authority, in his role as the Caliph of Islam. However, during the mid-19th Century, the Ottomans felt their hold on Hejaz threatened by the increasingly great foreign presence in the Red Sea region, notably the opening of the Suez Canal that made the sea into the world’s most strategically important shipping lane.
To shore up their position in Hejaz, in 1872 the Ottomans mounted a large-scale operation to retake all of North Yemen (especially Sana’a), while augmenting their presence in Asir. This resulted in an on-going rebellion against Ottoman rule by the Zaidi Imams of Sana’a that lasted until 1911, when the two sides made peace. From 1906, the Idrisi clan of Asir mounted a rebellion against Ottoman rule that dovetailed into WWI