the empire was very important, and built many castles and fortresses. some of them can still be seen, mostly in the southern part of somalia. there are also a number of pillar tombs, necropolises, and cities built during that era, which are now in ruins, which are attributed to ajuran engineers. during the ajuran period, many regions and people in the southern part of the horn of africa converted to islam because of the theocratic nature of the government. the royal family, the house of garen, expanded its territories and established its hegemonic rule through a skillful combination of warfare, trade linkages and alliances.