why did it happen?
Due to protests of Samyukta Maharashtra Movement and Mahagujarat Movement
Bombay State
Following protests of Samyukta Maharashtra Movement, in which 107 people were killed by police, Bombay State was reorganised on linguistic lines. Gujarati-speaking areas of Bombay State were partitioned into the state of Gujarat following Mahagujarat Movement. 
why mumbai is called financial capital of india It generates 6.16% of the total GDP what can you tell about the people of this place? A resident of Mumbai is called "Mumbaikar" in Marathi, in which the suffix "kar" means a "resident of" was it ever ruled by someone? Yes. Portuguese and British can you mention one of the feature of india after independence? After India's independence, the territory of the Bombay Presidency retained by India was restructured into Bombay State when did the above mentioned state came into existence? 1947 was this state dissolved? Yes. On 1 May 1960
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Bombay State [SEP] Dissolution of Bombay state
Bombay State was finally dissolved with the formation of Maharashtra and Gujarat states on 1 May 1960. Following protests of Samyukta Maharashtra Movement, in which 107 people were killed by police, Bombay State was reorganised on linguistic lines. Gujarati-speaking areas of Bombay State were partitioned into the state of Gujarat following Mahagujarat Movement. Maharashtra State with Bombay as its capital was formed with the merger of Marathi-speaking areas of Bombay State, eight districts from Central Provinces and Berar, five districts from Hyderabad State, and numerous princely states enclosed between them.