At the time of creation of Pakistan the world was looking a change in the political and economical system in all over the world and particularly, in Asia and Africa the struggle and movement for freedom and new socioeconomic relation was in its high spirit. Peoples power in Soviet Union getting strong and struggle in China for people's government was getting successes. In this background the Imperil powers of the world were not in favor in the creation of a new country and they fear it will be a success for the world movements. In this context they tried all their best to create hurdles in the movement of Pakistan. But it was a great vision of Quaid-E- Azam, who with all his hard working made it possible.
The struggle of Pakistan movement was actively participated by the different groups of Muslims in located in isolated parts having different culture and languages. It was clearly announce by the Muslim league about the future of the new federation and its composition. The formula for the peoples living other parts of India was agreed between the concerns powers for a one time migration rights to the peoples who opt it.
It was be also be mentioned that the majority of Urdu speaking groups were located in the other parts on India, which was not declared as a part of Pakistan, such as UP, CP, Bihar etc. They were benefited with the existing infrastructure on that regions and known as the educated class, whole got a considerable share in the government services and private services. There rivals were the majority Hindus who has developed the feeling of their overrepresentation. Their traditional trends were toward religious party's influenced by Saudi way of Islam. It was based on the strict view as they have contradiction with the Hindus on those regions. They were mostly having a great influence of Maulana Madoodadi, Maulana Madni, Maulana Azad etc who were not in favour in an independent country of Pakistan. In this view they were divided on the issue and many of them prefer to India. It was their fear about the survival of the new country.
On the other hand the Karachi in post independence era was the most developed City of the part of India declared as Pakistan. It was equipped with the tools of modern Town Planning and infrastructure for the development. All was contributed by the origin peoples of the city; mainly Parsi, Sindhi Hindus, Christen, Gugarti and other who were form the most part of the population at that time. There was no contradiction between these groups of Karachi and all were living in an atmosphere of brotherhood and were sincerely committed to a peace and respect for each other. The total population of the Karachi was well under half million at the time of independence.
The reason for selecting the Karachi as the capital of new country was the existing infrastructure of the city.
The migration process of 1947 revealed that there was a complete migration in the Punjab and Bangle and a considerable part of Sindhi (Hindus) from Karachi. There was Marginal migration of Urdu speaking peoples from the UP, CP, Bihar. Most of them prefer to the urban Sindh and particularly in Karachi. It is evident from the figure of 1951 record, which indicates the population of Karachi less then a million.
Now lets us consider the traditional cultural and difference in religious approaches of the other peoples of the country. The language difference was a contradiction mostly between Bengalis, Sindhs with the Urdu. The religious approach between the Punjab, Sindh in particular were. In Punjab and Sindh most of the Muslim population followed the traditional Sofism, which more related to the humanity in contradiction to the Urdu speaking majority following the religious approach of Saudia and their affiliated parties.
Their approach was accommodation which they demonstrated toward the immigrants in Punjab and Sindh. But when the circumstances changed then the sense of survivals developed in the deprived classes of the country against the Urdu speaking peoples.
The reasons mostly contributed the policies adopted after the death of Quaid-e-Azam and incapable of leadership of Muslim League.
In 1948 Urdu was instituted as the official national language of Pakistan even though only a pitifully small fraction of Pakistanis spoke the language. In the widely cited 1961 census results, it was reported that Urdu was the mother tongue of a mere 3.7% of all Pakistanis. The protest against the Urdu started in Bangal and the Language Movement began in 1948 and reached its climax in the killing of 21 February 1952, and ended in the adoption of Bangla as one of the state languages of Pakistan.
Since 1952, 21 February has been observed every year to commemorate the martyrs of the Language Movement. With UNESCO adopting a resolution on 17 November 1999 proclaiming 21 February as international mother language day. It is an honour bestowed by the international community on the Language Movement of Bengalis peoples.
It is a historical fact that the foundation of Bangladesh was laid in 1948 by the Urdu Language Bill by the Muslim League 1948.