Portugal was the first European power to establish factories and trading settlements in India in the early 16th century. In 1579–80, a Portuguese captain named Pedro Tavares received a firman from Mughal emperor to establish a city in Bengal for the Portuguese. The Portuguese were also allowed to preach their religion. As a consequence, a Portuguese colony was established at Hughli (in 1579 AD). The famous church of Bandel in Hooghly was built by the Portuguese.
The friendly attitude of Akbar towards the Portuguese was continued by his son and next Mughal emperor Jahangir.
Jahangir died in October 1627 and after a short interregnum marked by violent conflict among the other claimants for the throne, his son Shah Jahan became emperor in 1628 by eliminating all other possible contenders to the throne. Shahryar Mirza (youngest son of Jahangir), Dawar Bakhsh (Grandson of Jahangir and Khusrau’s eldest son), two sons of Akbar's son Daniyal (Tahmuras and Hushang) were all executed.
Shah Jahan was harbouring a grudge against the Portuguese as the latter did not side with him when he rebelled against his father Jahangir in 1622.
Added to this, the casus belli for the sack of Hooghly by Shah Jahan in 1932 was the abduction of two slave girls of his consort Mumtaz Mahal by the Portuguese in 1624 during the reign of Jahangir. The Portuguese, on the other hand, became involved with the slave trade. This was rankling in Shah Jahan's mind. Hence he ordered Bengal governor Qasim Khan to crush the Portuguese. In 1632 Qasim Khan captured Hooghly after three months. The Bandel church was burnt down during the sacking of Hooghly.
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