what difference occurred after independence here?
The region was organised into four states: Madras State, Mysore State, Hyderabad State and Travancore-Cochin.
South India
 the region was organised into four states: Madras State, Mysore State, Hyderabad State and Travancore-Cochin. 
which is the largest state in south by area UNANSWERABLE was this part of india ruled by any colonial power? The Europeans arrived in the 15th century and by the middle of the 18th century, the French and the British were involved in a protracted struggle for military control over the South India
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South India [SEP] Post-independence
After the independence of India in 1947, the region was organised into four states: Madras State, Mysore State, Hyderabad State and Travancore-Cochin. The States Reorganisation Act of 1956 reorganised the states on linguistic lines resulting in the creation of the new states of Andhra Pradesh, Karnataka, Kerala and Tamil Nadu. As a result of this Act, Madras State retained its name and Kanyakumari district was added to it from the state of Travancore-Cochin. The state was subsequently renamed Tamil Nadu in 1968. Andhra Pradesh was created through the merger of Andhra State with the Telugu-speaking districts of the Hyderabad State in 1956.