According to historians, the Aryans having settled in the Indus Valley and Western India carried on trade with Persia, Babylon and Egypt as early as 1000 BC from Salsette, present Kalyan. Upto the 4th century BC, Salsette enjoyed its prominence as the main commercial centre. Bombay (Mumbai) waspart of the Mauryan Empire under the great Buddhist Emperor Asoka (273-232 BC). After Asoka, it came under the Satavahana Kings. During this period, trade with foreign countries increased tremendously. Kalyan (Salsette) and Broach (Bharuch, in Gujarat) became the most important centres of trade with the Greeks, Scythians, Parthians etc. The Satavahana Kings could not hold on to Bombay for long because the Maurya and Chalukya dynasties came up successively as great powers. They had the capital at Mangalapuri, on the present Elephanta caves in the harbour.

Later, Bombay came under the Silhara kings (810-1260 AD). After this, it fell into the hands of Bhimadeva of Deccan. Towards the middle of the 14th century, Sultan Bahadur Shah of Gujarat attacked Bombay and captured it. By 1510, the Portuguese were becoming a force to be reckoned with. In 1534 a treaty was signed between the Sultan Bahadur Shah and the Portuguese, according to which Bassein and the nearby areas including Mumbai were ceded to D Joao III, King of Portugal. The Portuguese called it Bombaim or Good Bay, which is said to have become its name. These areas came under one Maestro Diogo. But in 1549, the islands were handed over in perpetuity to one Dr Gracia da Orta for an yearly rent.

In 1625, the An[lo-Dutch fleet captured Bombay Fort by a surprise attack and left as suddenly. In 1661, King Charles II of England married Princess Catherine de Braganza of Portugal. As part of the dowry he received 'Bombay'. In 1668 it was handed over to the East India Company. In 1857, there was a great national revolt which was put down. In 1858, by a special proclamation, the Administration of the country itself was taken over by the Queen of England, Queen Victoria, from th,e Company. A Viceroy was appointed to rule the country in the name of the Queen.

This period marks the tremendous growth of modern Mumbai. Politically, Bombay had come under the direct rule of the British. In 1861, the Bombay-Baroda (Mumbai -Vadodara) and Central Indian Railway opened its first section followed by the opening of the Broach (Bharuch) and Baroda (Vadodara) lines.

In the same year, the civil war broke out in America, which gave the biggest boost to cotton prices. Bombay made the most of it. This meant tremendous growth for the already existing commercial centres; along with this a large number of new enterprises were launched. These concerns along with the government were ultimately responsible for the Apollo Bunder, Mody Bay, Elphinstone, Mazagaon, Tank Bunder and Frere Reclamations of the east of the island and the Back Bay Reclamation from Colaba to the foot of Malabar Hill on the west. These were the forerunners of the present-day modern docks and harbour. Reclamation still continues.

The year 1864 marked the beginning of modern water supply and in 1885 Bombay was lit with gas. In the same year, the Indian National Congress was formed in Bombay. The entry of Mahatma Gandhi in 1920 into Indian politics proved a turning point and Mumbai played an important role in the political destiny of the country which finally gained Independence in 1947.