In the Central Zone Hindi-speaking areas, for a long time the prestige dialect was Braj Bhasha, but this was replaced in the 19th century by Dehlavi-based Hindustani. Hindustani was strongly influenced by Persian, with these and later Sanskrit influence leading to the emergence of Modern Standard Hindi and Modern Standard Urdu as registers of the Hindustani language. This state of affairs continued until the division of the British Indian Empire in 1947, when Hindi became the official language in India and Urdu became official in Pakistan. Despite the different script the fundamental grammar remains identical, the difference is more sociolinguistic than purely linguistic. Today it is widely understood/spoken as a second or third language throughout South Asia and one of the most widely known languages in the world in terms of number of speakers.