The Viá '' t Minh received control over the north , in a territory called Democratic Republic of Vietnam under Há '' `` ChÃ Minh . The area south of the 17th parallel was turned into State of Vietnam under Emperor Bá # o Ä á i. This was done to prevent Há '' `` ChÃ Minh from gaining control of the entire country . After the war , the Geneva Conference on July 21 , 1954 , made a provisional division of Vietnam at the 17th parallel , with control of the north given to the Viá '' t Minh as the Democratic Republic of Vietnam under Há '' `` ChÃ Minh , and the south becoming the State of Vietnam under Emperor Bá # o Ä á i , in order to prevent Há '' `` ChÃ Minh from gaining control of the entire country .