Diaspora refers to migratory settlers in foreign countries. Diaspora also refers to people who haveleft their homelands and settled in other parts of the world. It is because they were either forced to do so or they wanted to leave on their own. There are many other causes of diaspora. It basically happens because of imperialism, trade or labour migrations and globalization. Among the great diasporas of history is that of the Jewish people, who were forced to leave their lands in ancient times. The movement of Aryans from Central Europe to the Indian sub-continent thousand of years ago is also a noteworthy diaspora, although the causes of this diaspora are not clear. In twentieth century history, the Palestinian diaspora has attracted a lot of attention and been a cause of concern for worid leaders because of the plight of Palestinians. There have been massive diasporas in Africa, too, over the cemturies, either because of war or because of the savages of nature. British Bangladeshis, also known as British-Bengalis, are an important part of the Bengladeshi origin who are living abroad. Almost half of all British Bangladeshis live in London. especially in the East London boroughs, of which Tower Hamiets has the highest concentration. Today a tourist who is new to London may well decide to make his way over to the East End of the city, to visit ‘Banglatown’. Bangladeshis diaspora lives there. There is also Bangladeshi diaspora in Italy. They are mostly seen in Rome, Florence and Venice. Thought the scenario of Bangladeshi diaspora in East London is very appreciable, its scenario in Italy is not praiseworthy. The impacts of diaspora are very great. They either work or do business in foreign countries and play a very significant role in strengthening the economic frame of those countries. They give tax to government and build up a healthy economy of those countries. They are also found to get involved in politics and work to bring about massive development in those countries.