sentences:  In each province, the soldiers were under the supervision of a military commander known as an emir, and the coastal areas and the Indian ocean trade were protected by a navy.The European Age of discovery brought Europe's then superpower the Portuguese empire to the coast of East Africa, which at the time enjoyed a flourishing trade with foreign nations.The wealthy southeastern city-states of Kilwa, Mombasa, Malindi, Pate and Lamu were all systematically sacked and plundered by the Portuguese.