Hyderabad(telangana ) state was an independent state from 1948 to 1956..Hyderabad was the richest state when it was merged into andhra..Telangana ppl were hell bent on clubbing the state with andhra (which didn't even have a city to name as a capital also).But the shrewd politicians from andhra made false promised and they could influence the centre for the merger..
Even while the merging took place,Nehru announced that,ppl of telangana can separate as soon as there's some indifferenct..
Coming to the language,telangana telugu has many urdu words and the slang is totally different from the andhra telugu(its like Haryanvi and bihari)..
other districts(apart from telangana ) are very well developed with the funds from telangana state(hyderabad city in particular)..
Hyderabad was the richest and most developed city before the merger,now its 5th in the list..