 Throughout the 16th and 17th centuries successive Ajuran Empire defied the Portuguese economic monopoly in the Indian Ocean by employing a new coinage which followed the Ottoman pattern, thus proclaiming an attitude of economic independence in regard to the Portuguese.In the early modern period the Gobroon Dynasty, a Somali royal house ruled parts of Horn of Africa as a regional power during the 18th and 19th centuries.It was established by the Ajuran soldier Ibrahim Adeer, who had defeated various vassals of the collapsed Ajuran Empire and established the "House of Gobroon".