Horn of Africa Consequently, they lose their moisture before reaching Djibouti and Somalia, with the result that most of the Horn receives little rainfall during the monsoon season. In the mountains of Ethiopia, many areas receive over 2,000 mm (80 in) per year, and even Asmara receives an average of 570 mm (23 in). This rainfall is the sole source of water for many areas outside Ethiopia, including Egypt. In the winter, the northeasterly trade winds do not provide any moisture except in mountainous areas of northern Somalia, where rainfall in late autumn can produce annual totals as high as 500 mm (20
Horn of Africa the Adal Sultanate with Zeila as its headquarters dates back to at least the 9th or 10th century. According to I.M. Lewis, the polity was governed by local Somali dynasties, who also ruled over the similarly-established Sultanate of Mogadishu in the littoral Benadir region to the south. Adal's history from this founding period forth would be characterized by a succession of battles with neighbouring Abyssinia. Islam was introduced to the region early on from the Arabian peninsula, shortly after the hijra. At Muhammad's urging, a band of persecuted Muslims had fled across the Red Sea into the Horn. There, the