<P> Bombay , now called Mumbai , Bombaim in Portuguese , is the financial and commercial capital of India and one of the most populous cities in the world . At the time of arrival of the Portuguese , current Bombay was an archipelago of seven islands . Between the third century BCE and 1348 , the islands came under the control of successive Hindu dynasties . The Muslim rulers of Gujarat , who had been ruling current Thane and Vasai for a few decades , annexed the islands in 1348 , that were later governed by the Gujarat Sultanate from 1391 to 1534 . Growing apprehensive of the power of the Mughal emperor Humayun , Sultan Bahadur Shah of the Gujarat Sultanate was obliged to sign the Treaty of Bassein with the Portuguese Empire on 23 December 1534 . According to the treaty , the seven islands of Bombay , the nearby strategic town of Bassein and its dependencies were offered to the Portuguese . The territories were later surrendered on 25 October 1535 . </P>
by what name did the portuguese call the region that we now know as mumbai
Bombay