West Punjab
At Independence there was a Muslim majority in West Punjab with significant Hindu and Sikh minority. Nearly all of these minorities left West Punjab for India, to be replaced by large numbers of Muslims fleeing from the opposite direction. The official language of West Punjab was Urdu but most of the population spoke Punjabi using the Shahmukhi script. The linguist George Abraham Grierson in his multi volume Linguistic Survey of India (1904–1928) considered the various dialects up to then called "Western Punjabi", spoken in North, West, and South of Lahore in what is now Pakistani Punjab, as constituting instead a distinct language from Punjabi. (The local dialect of Lahore is the Majhi dialect of Punjabi, which has long been the basis of standard literary Punjabi.) Grierson proposed to name this putative language "Lahnda", and he dubbed as "Southern Lahnda" the coherent dialect cluster now known as Saraiki spoken in Multan Dera Ghazi Khan and Bahawalpur division and "North Lahnda" now known as Potwari spoken in Rawalpindi division and "Western Lahnda" now known as Hindko spoken in the regions bordering Khyber-Pakhtunkhwa.
East Pakistan Renaissance Society
The Muslim League and most other advocates of Pakistan had demanded a single state of Pakistan consisting of the British Indian provinces of Punjab, Khyber Pakhtunkhwa (then Northwest Frontier Province), Sindh, Balochistan and Bengal, and sought the Urdu language to be the only official language and "lingua franca" of Muslims. However, the East Pakistan Renaissance Society not only argued that Muslims were a separate nation from Hindus, it also advocated that the Bengali Muslims were distinct from the Muslims of other parts of India, on an ethnic, cultural and geographical basis. Unlike religion, the society argued that ethnicity and cultural differences cannot cross geographic boundaries. The society and its supporters in the Bengal Muslim League asserted that Bengali Muslims should constitute an independent state, as an "Eastern Pakistan" rather than part of a single state of Pakistan. The society asserted the importance of the Bengali culture and language, which many advocates of Pakistan criticised as being "Hinduised" and "Sanskritised."