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 Punjab
With effect from 1 November 1966, there was yet another reorganisation, this time on linguistic lines, when the state of Punjab as constituted in 1956 was divided into three: the mostly Hindi-speaking part became the present-day Indian state of Haryana and the mostly Punjabi-speaking part became the present-day Punjab, while a new union territory (Chandigarh) was also created, to serve as a capital to both states. At the same time, some parts of the former territory of Patiala and East Punjab States Union, including Solan and Nalagarh, were transferred into the state of Himachal Pradesh.